Principles of Consolidation - Additional Information (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) entity	Sep. 30, 2021 USD ($) entity partnership
Variable Interest Entity [Line Items]
Number of partnerships consolidated \| partnership		2
VIE, ownership interest rate (as a percent)		80.00%
Loans for sale at fair value that were acquired	$ 151	$ 151
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Number of partnerships consolidated \| partnership		2
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Number of entities called \| entity	2	6
Number of securitization entities to which asset transferred (in entities) \| entity	50	50
Unpaid principal balance of loans purchased	$ 66	$ 167
Gain related to called security	$ 6	$ 15
CAFL \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Number of entities called \| entity	0	1
Loans transferred to held-for-sale		$ 45

Loans Held-for-Sale, Fair Value, Acquired

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Number Of Partnerships Consolidated

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Unpaid Principal Balance Of Securitization Purchased

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Amount of reduction, resulting from a reclassification to held-for-sale, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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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.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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