Equity Activity in OCI (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
Net income	$ 1,888us-gaap_ProfitLoss	$ 5,325us-gaap_ProfitLoss
Other comprehensive income, net of tax effect:
Changes in net unrealized gains on AFS securities (net of tax of $13 and $184, respectively)	24	340
Reclassification adjustment for OTTI recognized in net income (net of tax of $60 and $18, respectively)	110	33
Reclassification adjustment for gains on AFS securities included in net income (net of tax of $121 and $-, respectively)	(225)	(1)
Other	(1)	0
Total other comprehensive (loss) income	(92)	372
Total comprehensive income	1,796	5,697
Other Comprehensive (Income) Loss Parenthetical Disclosures [Abstract]
Changes in net unrealized gains on AFS securities, tax	13	184
Reclassification adjustment for OTTI recognized in net income, tax	60	18
Reclassification adjustment for gains on AFS securities included in net income, tax	$ 121	$ 0

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

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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The change in other comprehensive income during the reporting period, net of tax, for an item that is not separately disclosed.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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