Derivatives - Derivatives Associated With Cash Flow Hedges and Mortgage Banking Hedges (Details) - Hedging Instruments And Hedged Items - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Cash Flow Hedge \| Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Variability in cash flows related to debt instruments (primarily loans)	$ 5,350	$ 5,350
Cash Flow Hedge \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Notional	5,350	5,350
Assets	0	0
Liabilities	20	71
Mortgage Banking Hedges \| Option contracts written
Derivative Instruments, Gain (Loss) [Line Items]
Notional	60	35
Assets	1	0
Liabilities	0	0
Mortgage Banking Hedges \| Forward contracts written
Derivative Instruments, Gain (Loss) [Line Items]
Notional	144	61
Assets	0	0
Liabilities	$ 1	$ 0

Held-to-maturity trust preferred loans.

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959

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- Definition

Fair value of all liability derivatives designated as cash flow hedging instruments.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ References

No definition available.

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- Definition

Aggregate fair value of all derivative liabilities designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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