Fair Value Measurements - Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
ASSETS
Mortgage loans held for sale	$ 893	$ 4,381
LIABILITIES
Mortgage servicing rights financing	19	10
Recurring Fair Value Measurements
ASSETS
Mortgage loans held for sale	893	4,381
MSRs - fair value	6,654	4,223
Equity investments	47	63
LIABILITIES
Mortgage servicing rights financing	19	10
Excess spread financing	509	768
Recurring Fair Value Measurements \| Level 1
ASSETS
Mortgage loans held for sale	0	0
MSRs - fair value	0	0
Equity investments	2	9
LIABILITIES
Mortgage servicing rights financing	0	0
Excess spread financing	0	0
Recurring Fair Value Measurements \| Level 2
ASSETS
Mortgage loans held for sale	819	4,381
MSRs - fair value	0	0
Equity investments		0
LIABILITIES
Mortgage servicing rights financing	0	0
Excess spread financing	0	0
Recurring Fair Value Measurements \| Level 3
ASSETS
Mortgage loans held for sale	74	0
MSRs - fair value	6,654	4,223
Equity investments	45	54
LIABILITIES
Mortgage servicing rights financing	19	10
Excess spread financing	509	768
IRLCs \| Recurring Fair Value Measurements
ASSETS
Derivative financial instruments	22	134
IRLCs \| Recurring Fair Value Measurements \| Level 1
ASSETS
Derivative financial instruments	0	0
IRLCs \| Recurring Fair Value Measurements \| Level 2
ASSETS
Derivative financial instruments	0	0
IRLCs \| Recurring Fair Value Measurements \| Level 3
ASSETS
Derivative financial instruments	22	134
Forward MBS trades \| Recurring Fair Value Measurements
ASSETS
Derivative financial instruments	8	7
LIABILITIES
Derivative financial instruments	9	8
Forward MBS trades \| Recurring Fair Value Measurements \| Level 1
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
Forward MBS trades \| Recurring Fair Value Measurements \| Level 2
ASSETS
Derivative financial instruments	8	7
LIABILITIES
Derivative financial instruments	9	8
Forward MBS trades \| Recurring Fair Value Measurements \| Level 3
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Recurring Fair Value Measurements
ASSETS
Derivative financial instruments	1	3
LIABILITIES
Derivative financial instruments	1	2
LPCs \| Recurring Fair Value Measurements \| Level 1
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Recurring Fair Value Measurements \| Level 2
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Recurring Fair Value Measurements \| Level 3
ASSETS
Derivative financial instruments	1	3
LIABILITIES
Derivative financial instruments	1	2
Swap futures \| Recurring Fair Value Measurements
LIABILITIES
Derivative financial instruments		6
Swap futures \| Recurring Fair Value Measurements \| Level 1
LIABILITIES
Derivative financial instruments		0
Swap futures \| Recurring Fair Value Measurements \| Level 2
LIABILITIES
Derivative financial instruments		6
Swap futures \| Recurring Fair Value Measurements \| Level 3
LIABILITIES
Derivative financial instruments		0
Treasury futures
LIABILITIES
Derivative financial instruments	14	$ 6
Treasury futures \| Recurring Fair Value Measurements
LIABILITIES
Derivative financial instruments	14
Treasury futures \| Recurring Fair Value Measurements \| Level 1
LIABILITIES
Derivative financial instruments	0
Treasury futures \| Recurring Fair Value Measurements \| Level 2
LIABILITIES
Derivative financial instruments	14
Treasury futures \| Recurring Fair Value Measurements \| Level 3
LIABILITIES
Derivative financial instruments	$ 0

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

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Fair value, before effects of master netting arrangements, of a financial asset or other 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. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value portion of mortgage loans held-for-sale.

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- Definition

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.

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