Fair Value Measurements - Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
ASSETS
Mortgage loans held for sale	$ 4,381	$ 5,720
LIABILITIES
Mortgage servicing rights financing	10	33
Fair Value, Recurring
ASSETS
Mortgage loans held for sale	4,381	5,720
Forward MSRs at fair value	4,223	2,703
Equity securities	63
LIABILITIES
Mortgage servicing rights financing	10	33
Excess spread financing	768	934
Fair Value, Recurring \| Level 1
ASSETS
Mortgage loans held for sale	0	0
Forward MSRs at fair value	0	0
Equity securities	9
LIABILITIES
Mortgage servicing rights financing	0	0
Excess spread financing	0	0
Fair Value, Recurring \| Level 2
ASSETS
Mortgage loans held for sale	4,381	5,720
Forward MSRs at fair value	0	0
Equity securities	0
LIABILITIES
Mortgage servicing rights financing	0	0
Excess spread financing	0	0
Fair Value, Recurring \| Level 3
ASSETS
Mortgage loans held for sale	0	0
Forward MSRs at fair value	4,223	2,703
Equity securities	54
LIABILITIES
Mortgage servicing rights financing	10	33
Excess spread financing	768	934
IRLCs \| Fair Value, Recurring
ASSETS
Derivative financial instruments	134	414
IRLCs \| Fair Value, Recurring \| Level 1
ASSETS
Derivative financial instruments	0	0
IRLCs \| Fair Value, Recurring \| Level 2
ASSETS
Derivative financial instruments	0	0
IRLCs \| Fair Value, Recurring \| Level 3
ASSETS
Derivative financial instruments	134	414
Forward MBS trades \| Fair Value, Recurring
ASSETS
Derivative financial instruments	7	37
LIABILITIES
Derivative financial instruments	8	156
Forward MBS trades \| Fair Value, Recurring \| Level 1
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
Forward MBS trades \| Fair Value, Recurring \| Level 2
ASSETS
Derivative financial instruments	7	37
LIABILITIES
Derivative financial instruments	8	156
Forward MBS trades \| Fair Value, Recurring \| Level 3
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Fair Value, Recurring
ASSETS
Derivative financial instruments	3	38
LIABILITIES
Derivative financial instruments	2	1
LPCs \| Fair Value, Recurring \| Level 1
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Fair Value, Recurring \| Level 2
ASSETS
Derivative financial instruments	0	0
LIABILITIES
Derivative financial instruments	0	0
LPCs \| Fair Value, Recurring \| Level 3
ASSETS
Derivative financial instruments	3	38
LIABILITIES
Derivative financial instruments	2	$ 1
Swap futures \| Fair Value, Recurring
LIABILITIES
Derivative financial instruments	6
Swap futures \| Fair Value, Recurring \| Level 1
LIABILITIES
Derivative financial instruments	0
Swap futures \| Fair Value, Recurring \| Level 2
LIABILITIES
Derivative financial instruments	6
Swap futures \| Fair Value, Recurring \| 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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