Investment Securities (Gains And Losses Related To Investment Securities) (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Investment Securities
Gross realized gains from sales of available-for-sale securities	$ 24	$ 110	$ 93	$ 313
Gross realized losses from sales of available-for-sale securities	(9)	(19)	(12)	(27)
Losses from other-than-temporary impairment	(25)	(132)	(104)	(612)
Losses not related to credit	15	58	48	388
Gains related to investment securities, net	5	17	25	62
Impairment associated with expected credit losses	(7)	(71)	(36)	(201)
Impairment associated with management's intent to sell the impaired securities prior to their recovery in value		(1)	(8)	(1)
Impairment associated with adverse changes in timing of expected future cash flows	(3)	(2)	(12)	(22)
Net impairment losses	$ (10)	$ (74)	$ (56)	$ (224)

Impairment associated with adverse changes in timing of expected future cash flows

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Impairment associated with expected credit losses

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Impairment associated with management's intent to sell the impaired securities prior to their recovery in value

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Noncredit portion of other-than-temporary impairments.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

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