v3.8.0.1
Derivative Instruments (Offsetting Assets and Liabilities) (Details) - USD ($)
$ in Millions
Dec. 31, 2017
Dec. 31, 2016
Derivatives    
Gross Amounts of Recognized Financial Instruments $ 10,807 $ 13,088
Securities purchased under agreement to resell    
Gross Amounts of Recognized Financial Instruments 240 1,016
Gross Amounts Offset in the Statements of Financial Position 0 0
Net Amounts Presented in the Statements of Financial Position 240 1,016
Financial Instruments/Collateral (240) (1,016)
Net Amount 0 0
Total Assets    
Gross Amounts of Recognized Financial Instruments 10,950 14,003
Gross Amounts Offset in the Statements of Financial Position (9,600) (11,716)
Net Amounts Presented in the Statements of Financial Position 1,350 2,287
Financial Instruments/Collateral (865) (1,415)
Net Amount 485 872
Derivatives    
Gross Amounts of Recognized Financial Instruments 5,955 6,290
Securities sold under agreement to repurchase    
Gross Amounts of Recognized Financial Instruments 8,400 7,606
Gross Amounts Offset in the Statement of Financial Position 0 0
Net Amounts Presented in the Statement of Financial Position 8,400 7,606
Financial Instruments/Collateral (8,400) (7,606)
Net Amount 0 0
Total Liabilities    
Gross Amounts of Recognized Financial Instruments 14,348 13,887
Gross Amounts Offset in the Statement of Financial Position (5,312) (5,945)
Net Amounts Presented in the Statement of Financial Position 9,036 7,942
Financial Instruments/Collateral (8,988) (7,905)
Net Amount 48 37
Counterparty    
Derivatives    
Gross Amounts of Recognized Financial Instruments 10,710 12,987
Gross Amounts Offset in the Statements of Financial Position (9,600) (11,716)
Net Amounts Presented in the Statements of Financial Position 1,110 1,271
Financial Instruments/Collateral (625) (399)
Net Amount 485 872
Derivatives    
Gross Amounts of Recognized Financial Instruments 5,948 6,281
Gross Amounts Offset in the Statement of Financial Position (5,312) (5,945)
Net Amounts Presented in the Statement of Financial Position 636 336
Financial Instruments/Collateral (588) (299)
Net Amount $ 48 $ 37