Derivative Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Asset derivatives
Asset derivatives gross amount	$ 87	$ 94
Derivative assets net amount on balance sheet	85us-gaap_DerivativeAssets	78us-gaap_DerivativeAssets
Derivative assets net amount		5
Liability derivatives
Liability derivatives gross amount	(385)	(367)
Derivative liabilities net amount on balance sheet	(383)us-gaap_DerivativeLiabilities	(361)us-gaap_DerivativeLiabilities
OTC derivatives
Asset derivatives
Asset derivatives gross amount	16	12
Offsets of derivative assets under counterparty netting	(4)	(22)
Derivative asset offsets under cash collateral received	(4)	17
Derivative assets net amount on balance sheet	8	7
Derivative assets pledged under securities collateral	(5)	(4)
Derivative assets net amount	3	3
Liability derivatives
Liability derivatives gross amount	(48)	(35)
Offsets of derivative liabilities under counterparty netting	4	22
Derivative liability offsets under cash collateral pledged	24	0
Derivative liabilities net amount on balance sheet	(20)	(13)
Derivative liabilities received under securities collateral	8	8
Derivative liabilities net amount	$ (12)	$ (5)

Represents the amount of counterparty netting under the master netting arrangements offset against derivative assets.

No definition available.

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- Definition

Represents the amount of derivative assets, net of offsets under the master netting arrangements and net of securities collateral.

+ References

No definition available.

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- Definition

Represents the amount of counterparty netting under the master netting arrangements offset against derivative liabilities.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of derivative liabilities, net of offsets under the master netting arrangements and net of securities collateral.

+ References

No definition available.

+ Details

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-Publisher FASB

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-Publisher FASB

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-Topic 210

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-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226008-175313

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- Definition

Amount of obligation to return securities collateral under master netting arrangements that have not been offset against derivative assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226016-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

+ Details

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- Definition

Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

+ Details

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

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-Publisher FASB

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-Topic 815

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-Paragraph 4B

-Subparagraph (a),(c)

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-Publisher FASB

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-Topic 210

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-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

+ Details

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

+ Details

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

+ Details

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- Definition

Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

+ References

+ Details

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