Fair Value Measurements - Level 3 Reconciliation (Details) - Recurring Fair Value Measurements - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Excess spread financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	$ 509	$ 768
Changes in fair value included in earnings	(10)	117
Purchases/additions (1)	0	0
Issuances	0	0
Sales/dispositions (2)	0	0
Repayments	4	(292)
Settlements	(36)	(61)
Other changes	0	0
Balance - end of period	459	532
Mortgage servicing rights financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	19	10
Changes in fair value included in earnings	4	14
Purchases/additions (1)	0	0
Issuances	0	0
Sales/dispositions (2)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of period	23	24
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	6,654	4,223
Changes in fair value included in earnings	(239)	663
Purchases/additions (1)	870	1,178
Issuances	133	360
Sales/dispositions (2)	(280)	(289)
Repayments	0	0
Settlements	0	0
Other changes	11	16
Balance - end of period	7,149	6,151
Mortgage loans held for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	74
Changes in fair value included in earnings	2
Purchases/additions (1)	47
Issuances	0
Sales/dispositions (2)	(54)
Repayments	2
Settlements	0
Other changes	0
Balance - end of period	67
Equity investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	45	54
Changes in fair value included in earnings	(3)	0
Purchases/additions (1)	0	0
Issuances	0	0
Sales/dispositions (2)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of period	42	54
IRLCs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	22	134
Changes in fair value included in earnings	8	(72)
Purchases/additions (1)	0	0
Issuances	0	0
Sales/dispositions (2)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of period	$ 30	$ 62

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Fair Value Changes

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Repayments

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Other Fair Value Changes

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Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Repayments

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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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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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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of purchases 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 sale 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 settlement 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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Fair value 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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Amount of purchases of financial instrument classified as a liability 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 sales of financial instrument classified as a liability 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 settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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