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Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2021 | Dec. 31, 2020
AFS securities [Abstract] |  |
AFS securities | $ 1,534,733 | $ 1,348,698
Equity securities | 32,806 | 30,737
Fair Value Measurements [Abstract] |  |
Collateral dependent impaired loans with specific reserve | 15,000 | 15,200
Reserves on collateral dependent impaired loans | $ 3,400 | 3,200
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% |
Federal Agency [Member] |  |
AFS securities [Abstract] |  |
AFS securities | $ 243,660 | 243,597
State & Municipal [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 58,068 | 43,180
Corporate [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 35,883 | 28,278
Recurring Basis [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 1,534,733 | 1,348,698
Equity securities | 32,806 | 30,737
Derivatives | 78,431 | 108,779
Total | 1,645,970 | 1,488,214
Liabilities [Abstract] |  |
Derivatives | 78,293 | 108,646
Total | 78,293 | 108,646
Recurring Basis [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Equity securities | 31,806 | 28,737
Derivatives | 0 | 0
Total | 31,806 | 28,737
Liabilities [Abstract] |  |
Derivatives | 0 | 0
Total | 0 | 0
Recurring Basis [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 1,534,733 | 1,348,698
Equity securities | 1,000 | 2,000
Derivatives | 78,431 | 108,779
Total | 1,614,164 | 1,459,477
Liabilities [Abstract] |  |
Derivatives | 78,293 | 108,646
Total | 78,293 | 108,646
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 | 243,660 | 243,597
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 | 243,660 | 243,597
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 | 58,068 | 43,180
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 | 58,068 | 43,180
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 | 685,483 | 595,839
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 | 685,483 | 595,839
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 | 511,639 | 437,804
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 | 511,639 | 437,804
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 | 35,883 | 28,278
Recurring Basis [Member] | Corporate [Member] | Level 1 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 0 | 0
Recurring Basis [Member] | Corporate [Member] | Level 2 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | 35,883 | 28,278
Recurring Basis [Member] | Corporate [Member] | Level 3 [Member] |  |
AFS securities [Abstract] |  |
AFS securities | $ 0 | $ 0

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