Guarantee Arrangements and Pledged Assets and Collateral - Net Credit Derivative Positions (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Carrying (Fair) Value [Member]
Credit Derivatives [Line Items]
Sell-protection credit derivative positions	$ 114		$ 545
Buy-protection credit derivative positions	186		505
Net position	(72)	[1]	40	[1]
Notional [Member]
Credit Derivatives [Line Items]
Sell-protection credit derivative positions	164,325		180,380
Buy-protection credit derivative positions	171,400		174,906
Net position	$ (7,075)	[1]	$ 5,474	[1]

[1] Positions are presented net in the table above to provide a complete analysis of our risk exposure and depict the way we manage our credit derivative portfolio. The offset of the sell-protection credit derivatives against the buy-protection credit derivatives may not be legally binding in the absence of master netting agreements with the same counterparty. Furthermore, the credit loss triggering events for individual sell protection credit derivatives may not be the same or occur in the same period as those of the buy protection credit derivatives thereby not providing an exact offset.