Derivatives, Net Gains (Losses) related to Cash Flow Hedges (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net Gains Losses Recognized Related to Derivatives in Cash Flow Hedging Relationships [Abstract]
Gains (pre tax) recognized in OCI on derivatives	$ 52	$ 190	$ 750
Gains (pre tax) reclassified from cumulative OCI into net income	388	571
Losses (pre tax) recognized in noninterest income on derivatives	$ (1)	$ (5)

Before tax amount of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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