Securitizations and Financings - Assets and Liabilities of Consolidated VIEs (Details) - Residential mortgage - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Assets - transfers accounted for as secured borrowings	$ 410	$ 488
Liabilities - transfers accounted for as secured borrowings	304	359
Restricted cash
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Assets - transfers accounted for as secured borrowings	40	47
Advances and other receivables, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Assets - transfers accounted for as secured borrowings	370	441
Advance facilities, net(1)
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Liabilities - transfers accounted for as secured borrowings	304	358
Payables and other liabilities
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Liabilities - transfers accounted for as secured borrowings	$ 0	$ 1

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No definition available.

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- Definition

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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