INVESTMENTS - Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Investments [Abstract]
Unrealized gains (losses) on securities available for sale	$ 2,272	$ 1,761
Unamortized unrealized gains on securities transferred to held to maturity	26	34
Deferred income taxes	(828)	(652)
Shareholders' equity, unrealized gains (losses) on investment securities	$ 1,470	$ 1,143

Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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