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Securities - Composition of Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | $ 779,133 | $ 680,056
Marketable equity securities | 5,150 | 4,816
Total Securities | 784,283 | 684,872
Debt Securities, Available-for-sale, Amortized Cost | 768,427 | 685,170
Debt Securities, Available-for-sale, Gross Unrealized Gains | 11,659 | 3,514
Debt Securities, Available-for-sale, Gross Unrealized Losses | (953) | (8,628)
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 10,040 | 9,736
Debt Securities, Available-for-sale, Amortized Cost | 9,969 | 9,958
Debt Securities, Available-for-sale, Gross Unrealized Gains | 71 | 0
Debt Securities, Available-for-sale, Gross Unrealized Losses | 0 | (222)
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 157,697 | 128,261
Debt Securities, Available-for-sale, Amortized Cost | 155,969 | 129,267
Debt Securities, Available-for-sale, Gross Unrealized Gains | 1,773 | 68
Debt Securities, Available-for-sale, Gross Unrealized Losses | (45) | (1,074)
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 189,348 | 148,659
Debt Securities, Available-for-sale, Amortized Cost | 186,879 | 149,849
Debt Securities, Available-for-sale, Gross Unrealized Gains | 2,773 | 795
Debt Securities, Available-for-sale, Gross Unrealized Losses | (304) | (1,985)
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 22,418 | 24,350
Debt Securities, Available-for-sale, Amortized Cost | 22,120 | 24,564
Debt Securities, Available-for-sale, Gross Unrealized Gains | 321 | 203
Debt Securities, Available-for-sale, Gross Unrealized Losses | (23) | (417)
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 275,870 | 246,784
Debt Securities, Available-for-sale, Amortized Cost | 273,771 | 251,660
Debt Securities, Available-for-sale, Gross Unrealized Gains | 2,680 | 0
Debt Securities, Available-for-sale, Gross Unrealized Losses | (581) | (4,876)
Corporate Obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 7,627 | 0
Debt Securities, Available-for-sale, Amortized Cost | 7,603 | 0
Debt Securities, Available-for-sale, Gross Unrealized Gains | 24 | 0
Debt Securities, Available-for-sale, Gross Unrealized Losses | 0 | 0
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, available-for-sale | 116,133 | 122,266
Debt Securities, Available-for-sale, Amortized Cost | 112,116 | 119,872
Debt Securities, Available-for-sale, Gross Unrealized Gains | 4,017 | 2,448
Debt Securities, Available-for-sale, Gross Unrealized Losses | $ 0 | $ (54)

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