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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 Thousands | Dec. 31, 2019 USD ($) month | Dec. 31, 2018 USD ($) month
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available-for-sale | $ 4,445,403 | $ 4,626,470
Loans held-for-sale | 14,033 | 16,273
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative liabilities, other | 22,795 | 31,540
Loans net of unearned income | 42,208 | 48,259
OREO, fair value | 15,660 | 22,387
Loans Held For Sale - SBA | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held-for-sale | 929 | 1,011
Other Assets | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets | $ 10,608 | $ 8,845
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
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 | 0.08
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 | 0.12
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 | 0.09 | 0.09
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 | 0.09 | 0.09
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 | 0.63
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 | 0.50 | 0.50
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 | 0.66 | 0.66
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 | $ 5,800,000 | $ 5,600,000
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 | 5,400,000 | 5,000,000
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 | $ 6,000,000 | $ 5,800,000
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 | 0.23
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 | 0.10
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 | 0.25
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 | 29 | 36
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 | 15 | 18
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 | 39 | 48
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 | 0.00 | 0.00
Other assets, measurement input | 0.00 | 0.00
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 | 0.10
Other assets, measurement input | 0.25 | 0.25
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 | 0.20
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 | 0.50
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 | 0.00 | 0.00
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 | 0.25
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 | 0.00 | 0.00
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 | 0.10
Adjustments to current sales yields for specific properties | Minimum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0.00 | 0.00
Adjustments to current sales yields for specific properties | Maximum | Discounted cash flow | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other assets, measurement input | 0.15 | 0.15
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 | $ 14,549 | $ 16,815
First Mortgages | 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 | 0.041 | 0.03
First Mortgages | 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 | 0.03 | 0.02
First Mortgages | 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 | 0.14 | 0.10
First Mortgages | 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 | 0.143 | 0.17
First Mortgages | 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 | 0.03 | 0.02
First Mortgages | 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 | 0.24 | 0.25
HELOC | 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 | 0.076 | 0.075
HELOC | 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 | 0.00 | 0.05
HELOC | 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 | 0.12
HELOC | 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 | 0.50 | 0.50
HELOC | 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 | 0.00 | 0.50
HELOC | 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 | 0.72 | 1.00
Interest-Only Strip (elected fair value) | Available-for-sale Securities | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available-for-sale | $ 19,136 | $ 9,902
Interest-Only Strip (elected fair value) | 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 Strip (elected fair value) | 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 | 0.12 | 0.11
Interest-Only Strip (elected fair value) | Constant prepayment rate | 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
Interest-Only Strip (elected fair value) | Constant prepayment rate | 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 |  | 0.12
Interest-Only Strip (elected fair value) | 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 | 0.16 | 0.14
Interest-Only Strip (elected fair value) | 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 | 0.16 | 0.14
Interest-Only Strip (elected fair value) | 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 | 0.17 |

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