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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 | Sep. 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 | $ 8,494 | $ 8,047
Loans held-for-sale | 301 | 405
Derivative liability | 130 | 125
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liability | 16 | 14
Loans net of unearned income | 86 | 77
OREO, fair value | 6 | 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 | $ 10 | $ 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 | 0.63 |
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 | 6 | 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 | 30 | 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 | 21 | 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 | $ 25 | $ 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 | 0.12 | 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 | 0.01 | 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 | 0.14 | 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 | 0.08 | 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 | $ 16 | $ 32
Interest- only strips- AFS | Constant prepayment rate | 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 | 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 | 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 | 0.10 |
Interest- only strips- AFS | Bond equivalent yield | 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 |  | 0.15
Interest- only strips- AFS | Bond equivalent yield | 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 |  | 0.17
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 | 0.10 | 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 | 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 |
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 |  | 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 |  | 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 | 0.08 | 0.07

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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 + Details
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