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Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
AFS securities [Abstract] |  |
AFS securities | $ 1,108,443 | $ 975,340
Equity securities | 29,223 | 27,771
Fair Value Measurements [Abstract] |  |
Reserves on collateral dependent impaired loans | $ 0 | 0
Minimum [Member] |  |
Fair Value Measurements [Abstract] |  |
Liquidation expense ratio on impaired collateral | 10.00% |
Maximum [Member] |  |
Fair Value Measurements [Abstract] |  |
Liquidation expense ratio on impaired collateral | 50.00% |
Recurring Basis [Member] |  |
AFS securities [Abstract] |  |
AFS securities | $ 1,108,443 | 975,340
Equity securities | 29,223 | 27,771
Derivatives | 128,968 | 41,766
Total | 1,266,634 | 1,044,877
Liabilities [Abstract] |  |
Derivatives | 128,986 | 41,777
Total | 128,986 | 41,777
Recurring Basis [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Equity securities | 25,223 | 23,771
Derivatives | 0 | 0
Total | 25,223 | 23,771
Liabilities [Abstract] |  |
Derivatives | 0 | 0
Total | 0 | 0
Recurring Basis [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 1,108,443 | 975,340
Equity securities | 4,000 | 4,000
Derivatives | 128,968 | 41,766
Total | 1,241,411 | 1,021,106
Liabilities [Abstract] |  |
Derivatives | 128,986 | 41,777
Total | 128,986 | 41,777
Recurring Basis [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Equity securities | 0 | 0
Derivatives | 0 | 0
Total | 0 | 0
Liabilities [Abstract] |  |
Derivatives | 0 | 0
Total | 0 | 0
Recurring Basis [Member] | Federal Agency [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 45,604 | 34,758
Recurring Basis [Member] | Federal Agency [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Federal Agency [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 45,604 | 34,758
Recurring Basis [Member] | Federal Agency [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | State & Municipal [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 2,689 | 2,513
Recurring Basis [Member] | State & Municipal [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | State & Municipal [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 2,689 | 2,513
Recurring Basis [Member] | State & Municipal [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Mortgage-Backed [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 516,581 | 503,626
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 516,581 | 503,626
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 533,432 | 434,443
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 533,432 | 434,443
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | $ 0
Recurring Basis [Member] | Corporate [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 10,137 |
Recurring Basis [Member] | Corporate [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 |
Recurring Basis [Member] | Corporate [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 10,137 |
Recurring Basis [Member] | Corporate [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | $ 0 |

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