| 
                                            
                                            
                                                Japan DLB: Lia: Trading: Securities: Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 2.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Cash and Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 230,667.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Cash and Deposits: Cash (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 9,015.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Cash and Deposits: Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 221,612.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Cash and Deposits: Cash: Checks and Bills (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 2,127.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Cash and Deposits: Deposits: Certificates of Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 160.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Call Loans (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 11,331.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Bills Purchased (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Monetary Claims Purchased (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 4,036.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Trading Account Securities (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 72.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Trading Account Bonds: Govt Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 15.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Trading Account Bonds: Local Govt Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 38.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Trading Assets (TA) (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 54,328.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Securities (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 592.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Securities: Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 6.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Securities: Related to Trading Trans (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 36.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Securities: Related to Trading Trans: Derivative (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 250.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Trading Related Financial Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 49,374.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: TA: Others (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 4,068.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Money Held in Trust (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 993.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Investment Securities (IS) (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 200,785.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Govt Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 78,269.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Local Govt Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 14,937.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Corporate Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 29,117.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Corporate Bonds: Public Corp Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 15,120.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Corporate Bonds: Bank Debentures (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 2,023.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Corporate Bonds: Industrial Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 11,972.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Stocks and Shares (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 16,421.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: IS: Foreign Securities (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 44,957.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Loans and Discounts (LD) (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 503,840.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Bills Discounts (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,345.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Bills Discounts: Commercial Bills (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,323.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Loans (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 502,494.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Loans: Loans on Bills (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 11,852.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Loans: Loans on Bills: To Other Financial Inst (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 8,203.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Loans: Loans on Deeds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 428,321.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: LD: Loans: Overdrafts (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 62,320.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Foreign Exchange (FX) (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 3,313.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: FX: Deposits with Foreign Banks (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,296.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: FX: Due from Foreign Banks (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 45.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: FX: Foreign Exchange Purchased (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,279.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: FX: Bills of Exchange Receivable (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 692.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others: Domestic Exchange Unsettled, Debit (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 21.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 59,383.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others: Suspense Payments (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 2,119.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others: Inter Office (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 27,408.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Debentures Deferred (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Customer's Liabilities for Acceptances & Guarantees (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 15,934.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Reserves for Possible Loan Losses (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 -2,994.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Mar 2000 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Reserves for Possible Investment Losses (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 -24.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Mar 2000 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Bond Trading with RA Trading Acc (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 156.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 2000 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others: Trading Related Financial Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 19,489.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 2000 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Others: Deferred Bond Issue Cost (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Mar 2000 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Deferred Tax Assets (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,675.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Mar 1999 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Assets: Deferred Tax Assets on Land Revaluation Excess (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Mar 1999 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 767,321.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Current Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 54,601.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Ordinary Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 423,441.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Savings Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 6,668.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Deposits at Notice (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 4,555.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Time Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 241,555.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Installment Savings (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 711.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Special Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 11,272.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Deposits for Tax Payments (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 84.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Non Resident Yen Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 2,657.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Foreign Currency Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 21,772.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Deposits: Financial Institutions' Deposits (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 47,845.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Certificates of Deposit: Negotiable (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 32,070.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Debentures (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 77.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Call Money (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 13,800.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Bills Sold (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Borrowed Money (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 62,775.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Borrowed Money: Bills Rediscounted (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Borrowed Money: From Other Banks (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 62,770.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                DLB: Lia: Borrowed Money: From Bank of Japan (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 40,748.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Borrowed Money: From Other Financial Institutions (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 20,573.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Foreign Exchange (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 3,405.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: FX: Due to Foreign Banks: Foreign Banks' Account (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 3,236.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: FX: Due to Foreign Banks (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 5.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: FX: Foreign Bills: Sold (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 19.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: FX: Foreign Bills: Payable (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 143.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Convertible Bonds (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 193.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Due to Trust Accounts (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 26,766.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Others: Domestic Exchange Unsettled, Credit (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 21.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Others (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 28,943.70
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Others: Suspense Receipts (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,600.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Others: Inter Office (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 1,916.30
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Reserve for Retirement Allowances (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 279.50
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Reserve for Employee Bonuses (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 92.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Sep 2001 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Other Reserves (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 356.90
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Reserves Under Special Law (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Acceptances and Guarantees (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 15,934.60
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Commercial Paper (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 44.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Sep 1998 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 49,283.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading: Securities: Sold for Short Sales (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 18.10
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading: Securities: Related to Sold for Short Sales Tran (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading: Securities: Related to Trading Trans: Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 240.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading: Related Financial Derivatives (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 49,021.80
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Trading: Others (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 0.00
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1997 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Straight Bond (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 11,259.40
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Apr 1998 - Feb 2018
                                     | 
                                
                            
                        
                            
                                
                                    
                                        
                                        
                                        | 
                                            
                                            
                                                Japan DLB: Lia: Net Assets (NA) (JPY bn)
                                            
                                         | 
                                    
                                    
                                        
                                        
                
                 49,009.20
            
                                        Feb 2018
                                     | 
                                    
                                    
                                    
                                        monthly
                                     | 
                                    
                                        Oct 1993 - Feb 2018
                                     |