Offsetting Arrangements - Liabilities With Enforceable Netting Arrangements (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Offsetting [Abstract]
Derivative, Net Amount of Liabilities Presented in Statement of Condition	$ 6,990	$ 6,308
Derivative, Counterparty Netting	0	0
Derivative, Collateral Provided	(110)	(19)
Derivative, Net Amount	6,880	6,289
Repurchase Agreements and Securities Lending, Net Amount of Liabilities Presented in Statement of Condition	17,311	15,405
Repurchase Agreements and Securities Lending, Counterparty Netting	(283)	(128)
Repurchase Agreements and Securities Lending, Collateral Provided	(15,274)	(13,872)
Repurchase Agreements and Securities Lending, Net Amount	1,754	1,405
Total, Net Amount of Liabilities Presented in Statement of Condition	24,301	21,713
Total, Counterparty Netting	(283)	(128)
Total, Collateral Provided	(15,384)	(13,891)
Total, Net Amount	$ 8,634	$ 7,694

Derivative Liability, Securities Sold under Agreements to Resell, and Securities Loaned Not Offset Against Collateral

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- Definition

Repurchase Agreements and Securities Lending, Fair Value, Amount Not Offset Against Collateral

+ References

No definition available.

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- Definition

Repurchase Agreements and Securities Loaned, Amount Offset Against Collateral

+ References

No definition available.

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- Definition

Repurchase Agreements and Securities Loaned, Collateral, Right to Reclaim Cash

+ References

No definition available.

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- Definition

Repurchase Agreements and Securities Loaned, Collateral, Right to Reclaim Securities

+ References

No definition available.

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- Definition

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

+ 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41678-113959

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- Definition

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

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- Definition

Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities 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 (c)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 10

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226006-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41678-113959

+ Details

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- Definition

Fair value, after effects of master netting arrangements, of 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 offset against the right to receive collateral. Includes liabilities 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 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 (e)

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41678-113959

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- Definition

Amount, after effects of master netting arrangements, of derivative liabilities, securities sold under agreements to repurchase and securities loaned offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities, securities sold under agreements to repurchase and securities loaned.

+ References

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- Definition

Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities, securities sold under agreements to repurchase and securities loaned.

+ References

+ Details

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