Fair Value - Schedule of Fair Value, Assets Measured on Nonrecurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 81	$ 99
Loans - collateral dependent loans	61,331	31,890
Mortgage and other servicing rights	35	23
Level 1 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	0	0
Loans - collateral dependent loans	0	0
Mortgage and other servicing rights	0	0
Level 2 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	65	99
Loans - collateral dependent loans	1,574	0
Mortgage and other servicing rights	0	0
Level 3 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	16	0
Loans - collateral dependent loans	59,757	31,890
Mortgage and other servicing rights	35	23
Fair Value, Nonrecurring \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	2
Loans - collateral dependent loans	109	3
Other real estate owned	39	34
Mortgage and other servicing rights	1	22
Fair Value Measurements	151	59
Fair Value, Nonrecurring \| Changes Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	0
Loans - collateral dependent loans	(8)	(2)
Other real estate owned	2	(4)
Mortgage and other servicing rights	1	3
Fair Value Measurements	(5)	(3)
Fair Value, Nonrecurring \| Level 1 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	0
Loans - collateral dependent loans	0	0
Other real estate owned	0	0
Mortgage and other servicing rights	0	0
Fair Value Measurements	0	0
Fair Value, Nonrecurring \| Level 2 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	0
Loans - collateral dependent loans	0	0
Other real estate owned	0	0
Mortgage and other servicing rights	0	0
Fair Value Measurements	0	0
Fair Value, Nonrecurring \| Level 3 \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	2
Loans - collateral dependent loans	109	3
Other real estate owned	39	34
Mortgage and other servicing rights	1	22
Fair Value Measurements	$ 151	$ 59

Other Real Estate Owned, Fair Value Disclosure

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- Definition

Servicing Assets, Fair Value Disclosure

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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