Fair Value Measurements - Reconciliation of Level 3 (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Excess spread financing \| Recurring Fair Value Measurements
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	$ 768	$ 934
Changes in fair value included in earnings	133	(10)
Purchases/additions (1)	0	0
Equity consideration received		0
Issuances	0	0
Sales/dispositions (1)	0	0
Repayments	(293)	(4)
Settlements	(99)	(152)
Other changes	0	0
Balance - end of year	509	768
Mortgage servicing rights financing \| Recurring Fair Value Measurements
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	10	33
Changes in fair value included in earnings	9	(23)
Purchases/additions (1)	0	0
Equity consideration received		0
Issuances	0	0
Sales/dispositions (1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	19	10
Mortgage servicing rights \| Recurring Fair Value Measurements
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	4,223	2,703
Changes in fair value included in earnings	549	(506)
Purchases/additions (1)	1,595	948
Equity consideration received		0
Issuances	554	1,077
Sales/dispositions (1)	(294)	(55)
Repayments	0	0
Settlements	0	0
Other changes	27	(56)
Balance - end of year	6,654	4,223
IRLCs \| Recurring Fair Value Measurements
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	134	414
Changes in fair value included in earnings	(112)	(280)
Purchases/additions (1)	0	0
Equity consideration received		0
Issuances	0	0
Sales/dispositions (1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	22	134
LPCs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Settlements		0
LPCs \| Recurring Fair Value Measurements
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	3	38
Changes in fair value included in earnings		(35)
Purchases/additions (1)		0
Equity consideration received		0
Issuances		0
Sales/dispositions (1)		0
Repayments		0
Other changes		0
Balance - end of year		3
Equity investments \| Recurring Fair Value Measurements
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	54	0
Changes in fair value included in earnings	(9)	(1)
Purchases/additions (1)	0	0
Equity consideration received		(55)
Issuances	0	0
Sales/dispositions (1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	45	54
Mortgage loans held for sale \| Recurring Fair Value Measurements
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	76
Changes in fair value included in earnings	(3)
Purchases/additions (1)	130
Issuances	0
Sales/dispositions (1)	(124)
Repayments	(2)
Settlements	0
Other changes	(3)
Balance - end of year	$ 74	$ 76

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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