Fair Value Measurements - Level 3 Reconciliation (Details) - Recurring Fair Value Measurements - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Excess spread financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	$ 768	$ 934
Changes in fair value included in earnings	117	14
Purchases	0	0
Issuances	0	0
Sales	0	0
Repayments	292
Settlements	(61)	(81)
Other changes	0	0
Balance - end of period	532	867
Mortgage servicing rights financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	10	33
Changes in fair value included in earnings	14	(12)
Purchases	0	0
Issuances	0	0
Sales	0	0
Repayments	0
Settlements	0	0
Other changes	0	0
Balance - end of period	24	21
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	4,223	2,703
Changes in fair value included in earnings	663	(190)
Purchases	1,178	218
Issuances	360	554
Sales	(289)	(12)
Repayments	0
Settlements	0	0
Other changes	16	34
Balance - end of period	6,151	3,307
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	54
Changes in fair value included in earnings	0
Purchases	0
Issuances	0
Sales	0
Repayments	0
Settlements	0
Other changes	0
Balance - end of period	54
IRLCs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	134	414
Changes in fair value included in earnings	(72)	(210)
Purchases	0	0
Issuances	0	0
Sales	0	0
Repayments	0
Settlements	0	0
Other changes	0	0
Balance - end of period	$ 62	$ 204

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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-Topic 820
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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 issuances 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 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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