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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 | Jun. 30, 2021 USD ($) month | Dec. 31, 2020 USD ($) month
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale at fair value | $ 8,388 | $ 8,047
Loans held-for-sale | 377 | 405
Derivative liability | 98 | 125
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability | 18 | 14
Loans net of unearned income | 66 | 77
OREO, fair value | 10 | 15
Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held for investment |  | 16
Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets | $ 11 | $ 9
Constant prepayment rate | Minimum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0
Constant prepayment rate | Maximum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0.26
Constant prepayment rate | Weighted Average | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0.11
Foreclosure losses | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.46 |
Foreclosure losses | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.65 |
Foreclosure losses | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.64 |
Constant default rate | Minimum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0
Constant default rate | Maximum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0.14
Constant default rate | Weighted Average | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0.01
Loss severity | Minimum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0
Loss severity | Maximum | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 1
Loss severity | Weighted Average | Discounted cash flow | Loans held for sale | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-investment, measurement input |  | 0.11
Visa covered litigation resolution amount | Minimum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input, value | $ 5,400 | $ 5,400
Visa covered litigation resolution amount | Maximum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input, value | 6,000 | 6,000
Visa covered litigation resolution amount | Weighted Average | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input, value | $ 5,800 | $ 5,800
Probability of resolution scenarios | Minimum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | 0.10 | 10
Probability of resolution scenarios | Maximum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | 0.50 | 50
Probability of resolution scenarios | Weighted Average | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | 0.16 | 0.16
Time until resolution | Minimum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | month | 9 | 3
Time until resolution | Maximum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | month | 33 | 27
Time until resolution | Weighted Average | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability, measurement input | month | 24 | 19
Marketability adjustments for specific properties | Minimum | Appraisals from comparable properties | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0 | 0
Marketability adjustments for specific properties | Minimum | Appraisals from comparable properties | Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0 | 0
Marketability adjustments for specific properties | Maximum | Appraisals from comparable properties | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0.10 | 10
Marketability adjustments for specific properties | Maximum | Appraisals from comparable properties | Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0.25 | 25
Borrowing base certificates adjustment | Minimum | Other collateral valuations | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0.20 | 20
Borrowing base certificates adjustment | Maximum | Other collateral valuations | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0.50 | 50
Financial Statements/Auction values adjustment | Minimum | Other collateral valuations | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0 | 0
Financial Statements/Auction values adjustment | Maximum | Other collateral valuations | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans net of unearned income, measurement input | 0.25 | 25
Adjustment for value changes since appraisal | Minimum | Appraisals from comparable properties | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
OREO measurement input | 0 | 0
Adjustment for value changes since appraisal | Maximum | Appraisals from comparable properties | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
OREO measurement input | 0.10 | 10
Adjustments to current sales yields for specific properties | Minimum | Discounted cash flow | Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0 | 0
Adjustments to current sales yields for specific properties | Maximum | Discounted cash flow | Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0.15 | 15
Residential Real Estate | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale | $ 26 | $ 13
Residential Real Estate | Prepayment Speeds | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.04 | 5
Residential Real Estate | Prepayment Speeds | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.13 | 15
Residential Real Estate | Prepayment Speeds | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.05 | 0.05
Residential Real Estate | Foreclosure losses | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input |  | 59
Residential Real Estate | Foreclosure losses | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input |  | 70
Residential Real Estate | Foreclosure losses | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input |  | 0.63
Residential Real Estate | Loss severity | Minimum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.02 | 3
Residential Real Estate | Loss severity | Maximum | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.16 | 19
Residential Real Estate | Loss severity | Weighted Average | Discounted cash flow | Loans Held For Sale, Residential Real Estate | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.10 | 0.12
Interest- only strips- AFS | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale at fair value | $ 30 | $ 32
Interest- only strips- AFS | Constant prepayment rate | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input |  | 0.12
Interest- only strips- AFS | Constant prepayment rate | Minimum | Discounted cash flow | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.11 |
Interest- only strips- AFS | Constant prepayment rate | Maximum | Discounted cash flow | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.12 |
Interest- only strips- AFS | Constant prepayment rate | Weighted Average | Discounted cash flow | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.11 | 0.12
Interest- only strips- AFS | Bond equivalent yield | Minimum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.11 | 0.15
Interest- only strips- AFS | Bond equivalent yield | Maximum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.13 | 0.17
Interest- only strips- AFS | Bond equivalent yield | Weighted Average | Discounted cash flow | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.11 | 0.15
SBAs | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale | $ 1 | $ 1
SBAs | Constant prepayment rate | Minimum | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.08 | 8
SBAs | Constant prepayment rate | Maximum | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.12 | 12
SBAs | Constant prepayment rate | Weighted Average | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.10 | 0.10
SBAs | Bond equivalent yield | Minimum | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.15 | 7
SBAs | Bond equivalent yield | Maximum | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.16 | 8
SBAs | Bond equivalent yield | Weighted Average | Discounted cash flow | Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale, measurement input | 0.15 | 0.07

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