Fair Value Measurements - Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Mortgage loans held for sale	$ 927	$ 893
LIABILITIES
Mortgage servicing rights financing	29	19
Recurring Fair Value Measurements
ASSETS
Mortgage loans held for sale	927	893
MSRs at fair value	9,090	6,654
Equity investments	9	47
LIABILITIES
Mortgage servicing rights financing	29	19
Excess spread financing	437	509
Recurring Fair Value Measurements \| Level 1
ASSETS
Mortgage loans held for sale	0	0
MSRs at fair value	0	0
Equity investments	1	2
LIABILITIES
Mortgage servicing rights financing	0	0
Excess spread financing	0	0
Recurring Fair Value Measurements \| Level 2
ASSETS
Mortgage loans held for sale	846	819
MSRs at fair value	0	0
Equity investments	0	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	81	74
MSRs at fair value	9,090	6,654
Equity investments	8	45
LIABILITIES
Mortgage servicing rights financing	29	19
Excess spread financing	437	509
IRLCs \| Recurring Fair Value Measurements
ASSETS
Fair Value	21	22
IRLCs \| Recurring Fair Value Measurements \| Level 1
ASSETS
Fair Value	0	0
IRLCs \| Recurring Fair Value Measurements \| Level 2
ASSETS
Fair Value	0	0
IRLCs \| Recurring Fair Value Measurements \| Level 3
ASSETS
Fair Value	21	22
Forward MBS trades \| Recurring Fair Value Measurements
ASSETS
Fair Value	22	8
Fair Value	9	9
Forward MBS trades \| Recurring Fair Value Measurements \| Level 1
ASSETS
Fair Value	0	0
Fair Value	0	0
Forward MBS trades \| Recurring Fair Value Measurements \| Level 2
ASSETS
Fair Value	22	8
Fair Value	9	9
Forward MBS trades \| Recurring Fair Value Measurements \| Level 3
ASSETS
Fair Value	0	0
Fair Value	0	0
Treasury futures
ASSETS
Fair Value		14
Treasury futures \| Recurring Fair Value Measurements
ASSETS
Fair Value	113
Fair Value		14
Treasury futures \| Recurring Fair Value Measurements \| Level 1
ASSETS
Fair Value	0
Fair Value		0
Treasury futures \| Recurring Fair Value Measurements \| Level 2
ASSETS
Fair Value	113
Fair Value		14
Treasury futures \| Recurring Fair Value Measurements \| Level 3
ASSETS
Fair Value	0
Fair Value		0
LPCs \| Recurring Fair Value Measurements
ASSETS
Fair Value	3	1
Fair Value		1
LPCs \| Recurring Fair Value Measurements \| Level 1
ASSETS
Fair Value	0	0
Fair Value		0
LPCs \| Recurring Fair Value Measurements \| Level 2
ASSETS
Fair Value	0	0
Fair Value		0
LPCs \| Recurring Fair Value Measurements \| Level 3
ASSETS
Fair Value	$ 3	1
Fair Value		$ 1

Excess spread financing (at fair value)

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- Definition

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

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- Definition

Fair value of 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, not subject to a master netting arrangement.

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- Definition

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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- Definition

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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