Securities - Other than Temporary Impairment, Credit Losses Recognized in Earnings (Details) (Held-to-maturity Securities [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Held-to-maturity Securities [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning balance of credit losses on held-to-maturity debt securities for which a portion of an other-than-temporary impairment was recognized in other comprehensive income (loss)	$ 61,000,000	$ 0
Credit losses previously recognized on held-to-maturity debt securities of a VIE consolidated during 2013	0	61,000,000
Increase in credit losses for which an other-than-temporary impairment was previously recognized	11,000,000	0
Reduction of credit losses previously recognized on held-to-maturity debt securities due to closure of a VIE	(72,000,000)	0
Ending balance of credit losses on held-to-maturity debt securities for which a portion of an other-than-temporary impairment was recognized in other comprehensive income (loss)	$ 0	$ 61,000,000

Credit losses previously recognized on held-to-maturity debt securities of a VIE consolidated during 2013

No definition available.

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- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

+ Details

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

+ Details

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- Definition

The change during the reporting period in the cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

+ Details

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- Details

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