Variable Interest Entities - Re-securitizations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Transfers of securities to VIEs
Firm-sponsored private-label	$ 0	$ 0	$ 647
Agency	15,532	12,617	$ 11,241
Variable Interest Entity [Line Items]
Assets held in VIEs with continuing involvement	183,040	182,763
Firm-sponsored private-label \| Nonconsolidated entities
Variable Interest Entity [Line Items]
Assets held in VIEs with continuing involvement	118	783
Interest in VIEs	10	29
Agency \| Nonconsolidated entities
Variable Interest Entity [Line Items]
Interest in VIEs	$ 3,058	$ 2,250

Amount of securities transferred to agency re-securitization VIEs during the period.

No definition available.

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- Definition

Amount of securities transferred to private-label re-securitization VIEs during the period.

+ References

No definition available.

+ Details

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- Definition

Variable Interest Entity, Transfer of Securities [Abstract]

+ References

No definition available.

+ Details

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107314-111719

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

+ References

No definition available.

+ Details

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