Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 1,081	$ 1,105	$ 3,429	$ 3,269
Other comprehensive income (loss) before taxes:
Net unrealized gains (losses) on securities available for sale	(104)	1,107	394	(849)
Net unrealized gains (losses) on securities held to maturity	35	(1,465)	96	(1,465)
Net unrealized gains (losses) on cash flow hedges	(107)	84	37	(195)
Foreign currency translation adjustments	(41)	124	25	(19)
Other	6	(1)	2	6
Other comprehensive income (loss) before taxes	(211)	(151)	554	(2,522)
Income tax provision (benefit) related to other comprehensive income	(23)	(104)	241	(944)
Other comprehensive income (loss), net of tax	(188)	(47)	313	(1,578)
Comprehensive income	$ 893	$ 1,058	$ 3,742	$ 1,691

Other Comprehensive Income (Loss), Other, Before Tax, Attributable To Parent

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Other Comprehensive Income (Loss) Securities Transferred To Held To Maturity Adjustment Before Tax Portion Attributable To Parent

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, on foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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