Mortgage Servicing Rights and Related Liabilities - MSRs and Related Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Mortgage Servicing Rights [Line Items]
Forward MSRs - fair value	$ 2,703	$ 3,496
Mortgage servicing rights	2,708	3,502
Mortgage servicing liabilities - amortized cost	41	61
MSR related liabilities - nonrecourse at fair value	967	1,348
Mortgage Servicing Rights
Mortgage Servicing Rights [Line Items]
Forward MSRs - fair value	2,703	3,496
Reverse MSRs - amortized cost	5	6
Mortgage servicing rights	2,708	3,502
Mortgage servicing liabilities - amortized cost	41	61
Mortgage Servicing Right Liability
Mortgage Servicing Rights [Line Items]
Mortgage servicing liabilities - amortized cost	41	61	$ 71
Excess spread financing - fair value	934	1,311
Mortgage servicing rights financing - fair value	33	37
MSR related liabilities - nonrecourse at fair value	$ 967	$ 1,348

Excess Spread Financing, Fair Value Disclosure

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- Definition

Mortgage Servicing Rights Liability Resulting from Sale or Securitization of Servicer Advances, Rights not Accounted for as a Sale

+ References

No definition available.

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- Definition

Mortgage Servicing Rights [Line Items]

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Mortgage Serving Rights Liability, carried at fair value

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

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- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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- Definition

Amortized amount of contract to service financial assets under which estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenue are not expected to adequately compensate the servicer for performing the servicing.

+ References

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