Derivative Instruments - Credit and Liquidity Risk and Related Contingent Features (Details 3) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Credit and liquidity risk, credit-related contingent features
Net derivative payables containing collateral or termination feature, Fair Value	$ 40,212	$ 40,844
Net derivative payables posted collateral	33,642	34,414
Single-notch ratings downgrade
Credit and liquidity risk, credit-related contingent features
Additional collateral to be posted by the Firm as the impact of ratings downgrades	1,114	1,234
Additional assets required to settle trades as the impact of ratings downgrades	797	857
Two-notch ratings downgrade
Credit and liquidity risk, credit-related contingent features
Additional collateral to be posted by the Firm as the impact of ratings downgrades	3,702	4,090
Additional assets required to settle trades as the impact of ratings downgrades	$ 1,162	$ 1,270