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Securities - Composition of Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | $ 909,651 | $ 770,393
Marketable equity securities | 1,142 | 3,300
Total Securities | 910,793 | 773,693
Total Debt Securities, Available-for-sale, Amortized Cost | 900,235 | 737,005
Gross Unrealized Gains | 15,183 | 33,478
Gross Unrealized Losses | (5,767) | (90)
Fair Value | 909,651 | 770,393
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 95,327 | 10,282
Total Debt Securities, Available-for-sale, Amortized Cost | 95,954 | 9,980
Gross Unrealized Gains | 115 | 302
Gross Unrealized Losses | (742) | 0
Fair Value | 95,327 | 10,282
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 70,348 | 82,904
Total Debt Securities, Available-for-sale, Amortized Cost | 68,599 | 78,755
Gross Unrealized Gains | 1,749 | 4,149
Gross Unrealized Losses | 0 | 0
Fair Value | 70,348 | 82,904
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 270,294 | 209,296
Total Debt Securities, Available-for-sale, Amortized Cost | 270,696 | 202,975
Gross Unrealized Gains | 2,408 | 6,410
Gross Unrealized Losses | (2,810) | (89)
Fair Value | 270,294 | 209,296
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 56,793 | 67,778
Total Debt Securities, Available-for-sale, Amortized Cost | 57,029 | 66,960
Gross Unrealized Gains | 392 | 818
Gross Unrealized Losses | (628) | 0
Fair Value | 56,793 | 67,778
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 341,300 | 273,681
Total Debt Securities, Available-for-sale, Amortized Cost | 336,918 | 258,875
Gross Unrealized Gains | 5,969 | 14,806
Gross Unrealized Losses | (1,587) | 0
Fair Value | 341,300 | 273,681
Corporate Obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 500 | 2,025
Total Debt Securities, Available-for-sale, Amortized Cost | 500 | 2,021
Gross Unrealized Gains | 0 | 5
Gross Unrealized Losses | 0 | (1)
Fair Value | 500 | 2,025
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities available-for-sale | 75,089 | 124,427
Total Debt Securities, Available-for-sale, Amortized Cost | 70,539 | 117,439
Gross Unrealized Gains | 4,550 | 6,988
Gross Unrealized Losses | 0 | 0
Fair Value | $ 75,089 | $ 124,427

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