Fair Value of Assets and Liabilities - Schedule Of Unobservable Inputs Utilized In Determining The Fair Value Of Level 3 Recurring And Non-Recurring Measurements (Details) $ in Millions	Mar. 31, 2024 USD ($) month	Dec. 31, 2023 USD ($) month
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale at fair value	$ 8,148	$ 8,391
Loans held-for-sale	84	68
Derivative Liabilities, fair value	795	675
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities, fair value	20	23
Loans and leases, fair value	244	245
OREO, fair value	4	4
Level 3 | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		90
Level 3 | Residential Real Estate | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	14	26
Level 3 | Interest-only strips | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale at fair value	$ 19	$ 13
Constant prepayment rate | Level 3 | Interest-only strips | Minimum | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.14	0.14
Constant prepayment rate | Level 3 | Interest-only strips | Maximum | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.20	0.15
Constant prepayment rate | Level 3 | Interest-only strips | Weighted Average | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.14	0.14
Bond equivalent yield | Level 3 | Interest-only strips | Minimum | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.16	0.18
Bond equivalent yield | Level 3 | Interest-only strips | Maximum | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.20	0.21
Bond equivalent yield | Level 3 | Interest-only strips | Weighted Average | Discounted cash flow | Trading Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available-for-sale, measurement input	0.19	0.18
Prepayment speeds - First mortgage | Level 3 | Loans held for sale—first mortgages | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.02	0.02
Prepayment speeds - First mortgage | Level 3 | Loans held for sale—first mortgages | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.06	0.07
Prepayment speeds - First mortgage | Level 3 | Loans held for sale—first mortgages | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.03	0.03
Foreclosure losses | Level 3 | Residential Real Estate | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.63	0.64
Foreclosure losses | Level 3 | Residential Real Estate | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.67	0.68
Foreclosure losses | Level 3 | Residential Real Estate | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.65	0.65
Loss severity trends - First mortgage | Level 3 | Loans held for sale—first mortgages | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0	0
Loss severity trends - First mortgage | Level 3 | Loans held for sale—first mortgages | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.02	0.03
Loss severity trends - First mortgage | Level 3 | Loans held for sale—first mortgages | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.01	0.02
Visa covered litigation resolution amount | Level 3 | Minimum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input, value	$ 5,700	$ 5,700
Visa covered litigation resolution amount | Level 3 | Maximum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input, value	6,700	6,700
Visa covered litigation resolution amount | Level 3 | Weighted Average | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input, value	$ 6,300	$ 6,300
Probability of resolution scenarios | Level 3 | Minimum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input	0.10	0.10
Probability of resolution scenarios | Level 3 | Maximum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input	0.25	25
Probability of resolution scenarios | Level 3 | Weighted Average | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input	0.18	0.18
Time until resolution | Level 3 | Minimum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input | month	3	6
Time until resolution | Level 3 | Maximum | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input | month	33	36
Time until resolution | Level 3 | Weighted Average | Discounted cash flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, measurement input | month	22	24
Marketability adjustments for specific properties | Level 3 | Minimum | Appraisals from comparable properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0	0
Marketability adjustments for specific properties | Level 3 | Minimum | Appraisals from comparable properties | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets, measurement input		0
Marketability adjustments for specific properties | Level 3 | Maximum | Appraisals from comparable properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0.25	0.25
Marketability adjustments for specific properties | Level 3 | Maximum | Appraisals from comparable properties | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets, measurement input		25
Borrowing base certificates liquidation adjustment | Level 3 | Minimum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0.25	0.25
Borrowing base certificates liquidation adjustment | Level 3 | Maximum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0.50	0.50
Adjustment for value changes since appraisal | Level 3 | Minimum | Appraisals from comparable properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
OREO measurement input	0	0
Adjustment for value changes since appraisal | Level 3 | Maximum | Appraisals from comparable properties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
OREO measurement input	0.10	0.10
Measurement Input, Adjustments To Current Sales Yields For Specific Properties | Level 3 | Minimum | Discounted cash flow | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets, measurement input		0
Measurement Input, Adjustments To Current Sales Yields For Specific Properties | Level 3 | Maximum | Discounted cash flow | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets, measurement input		0.15
Auction appraisals marketability adjustment | Level 3 | Minimum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0	0
Auction appraisals marketability adjustment | Level 3 | Maximum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0.10	0.10
Financial Statements liquidation adjustment | Level 3 | Minimum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	0.50	0.50
Financial Statements liquidation adjustment | Level 3 | Maximum | Other collateral valuations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, measurement input	1	1