Securities (Details 5) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Securities held to maturity
Securities held to maturity, Amortized Cost	$ 5,601	$ 1,115
Securities held to maturity, Gross Unrealized Gains, Recognized in Other Comprehensive Income (OCI)	8	5
Securities held to maturity, Gross Unrealized Losses, Recognized in Other Comprehensive Income (OCI)	163	17
Total securities held to maturity, Carrying Amount	5,446	1,103
Securities held to maturity, Gross Unrealized Gains, Not Recognized in OCI	26	32
Securities held to maturity, Gross Unrealized Losses, Not Recognized in OCI	22
Total securities held to maturity, Fair Value	5,450	1,135
Residential mortgage-backed securities, U.S. government agency and government sponsored agencies
Securities held to maturity
Securities held to maturity, Amortized Cost	3,983	997
Securities held to maturity, Gross Unrealized Gains, Recognized in Other Comprehensive Income (OCI)	8	5
Securities held to maturity, Gross Unrealized Losses, Recognized in Other Comprehensive Income (OCI)	68
Total securities held to maturity, Carrying Amount	3,923	1,002
Securities held to maturity, Gross Unrealized Gains, Not Recognized in OCI	13	12
Securities held to maturity, Gross Unrealized Losses, Not Recognized in OCI	21
Total securities held to maturity, Fair Value	3,915	1,014
Commercial mortgage-backed securities
Securities held to maturity
Securities held to maturity, Amortized Cost	1,609
Securities held to maturity, Gross Unrealized Losses, Recognized in Other Comprehensive Income (OCI)	94
Total securities held to maturity, Carrying Amount	1,515
Securities held to maturity, Gross Unrealized Gains, Not Recognized in OCI	11
Securities held to maturity, Gross Unrealized Losses, Not Recognized in OCI	1
Total securities held to maturity, Fair Value	1,525
CLOs
Securities held to maturity
Securities held to maturity, Amortized Cost	9	118
Securities held to maturity, Gross Unrealized Losses, Recognized in Other Comprehensive Income (OCI)	1	17
Total securities held to maturity, Carrying Amount	8	101
Securities held to maturity, Gross Unrealized Gains, Not Recognized in OCI	2	20
Total securities held to maturity, Fair Value	$ 10	$ 121

Amount of accumulated unrecognized gain on investments in held-to-maturity securities recognized in earnings.

No definition available.

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Amount of accumulated unrecognized loss on investments in held-to-maturity securities recognized in earnings, including the amount of other than temporary impairment losses.

+ References

No definition available.

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Purchase cost of investments in debt securities categorized as held-to-maturity adjusted for any accretion or amortization of purchase premium or discount, less principal payments and any impairment previously recognized in earnings.

+ References

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Unrealized holding gain on securities transferred to held-to-maturity securities classification as of the transfer date, net of amortization and other-than-temporary impairments recognized subsequent to the date of transfer.

+ References

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Unrealized holding loss on securities transferred to held-to-maturity securities classification as of the transfer date, net of amortization and other-than-temporary impairments recognized subsequent to the date of transfer.

+ References

No definition available.

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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Fair value of investments in debt securities classified as held-to-maturity.

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