Fair Value Measurements - Roll Forward of Financial Instruments Classified as Level 3 (Details) - Recurring - Level 3 - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Assets
Balance at Beginning of Period	$ 445	$ 539
Total Gains (Losses) Recorded in Earnings	(135)	(135)
Purchases / Closings	193	270
Sales	0	0
Settlement	0	0
Transfers Out	16	(170)
Balance at End of Period	519	504
(Dollars in millions)
Balance at Beginning of Period		(35)
Total Gains (Losses) Recorded in Earnings		(35)
Purchases / Closings		0
Sales		0
Settlement		0
Transfers Out		0
Balance at End of Period		(70)
Home equity
Assets
Balance at Beginning of Period		2
Total Gains (Losses) Recorded in Earnings		0
Purchases / Closings		0
Sales		0
Settlement		0
Transfers Out		0
Balance at End of Period		2
Mortgage servicing rights
Assets
Balance at Beginning of Period	392	329
Total Gains (Losses) Recorded in Earnings	39	34
Purchases / Closings	92	65
Sales	0	0
Settlement	0	0
Transfers Out	0	0
Balance at End of Period	523	428
Rate lock commitments
Assets
Balance at Beginning of Period	53	208
Total Gains (Losses) Recorded in Earnings	(174)	(169)
Purchases / Closings	101	205
Sales	0	0
Settlement	0	0
Transfers Out	16	(170)
Balance at End of Period	$ (4)	74
DOJ Liability
(Dollars in millions)
Balance at Beginning of Period		(35)
Total Gains (Losses) Recorded in Earnings		(35)
Purchases / Closings		0
Sales		0
Settlement		0
Transfers Out		0
Balance at End of Period		$ (70)

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

No definition available.

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- Definition

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

+ References

No definition available.

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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
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

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.

+ References

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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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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

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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- Definition

Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

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.

+ References

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-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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