Derivative Positions (Additional Information) (Detail) - USD ($) shares in Millions, $ in Millions	1 Months Ended
	May 31, 2009	Jun. 30, 2016		Dec. 31, 2015
Derivative Asset, Notional Amount		$ 136,166		$ 123,025
Derivative Liability, Notional Amount		137,664		123,514
Credit Risk Contract [Member]
Derivative Asset, Notional Amount		6		6
Derivative Liability, Notional Amount		8	[1],[2]	9
Derivative Financial Instruments, Liabilities [Member] | Visa Interest [Member]
Number Of Shares Sold To Selected Financial Institutions	3.2
Visa Interest [Member] | Other Contract [Member]
Derivative Liability, Notional Amount		49	[1],[2]	49
Interest rate futures [Member] | Mortgage Servicing Rights [Member]
Derivative Liability, Notional Amount		16,500		9,100
Interest rate futures [Member] | Loans Held For Sale [Member]
Derivative Asset, Notional Amount				518
Derivative Liability, Notional Amount		540
Interest rate futures [Member] | Other Trading [Member]
Derivative Asset, Notional Amount		12,000		12,600
Equity futures [Member] | Equity Contract [Member]
Derivative Asset, Notional Amount		$ 846		$ 329

[1] Amount includes $9.1 billion of notional amounts related to interest rate futures. These futures contracts settle in cash daily, one day in arrears. The derivative asset or liability associated with the one day lag is included in the fair value column of this table.

[2] See “Economic Hedging and Trading Activities” in this Note for further discussion.