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Securities - Fair Values and Amortized Costs Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
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Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | $ 652,785 | $ 685,170
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 11,816 | 3,514
Debt Securities, Available-for-Sale, Gross Unrealized Losses | (564) | (8,628)
Debt Securities, Available-for-Sale, Fair Value | 664,037 | 680,056
Marketable equity securities | 4,551 | 4,816
Total Securities | 668,588 | 684,872
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 9,964 | 9,958
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 43 | 0
Debt Securities, Available-for-Sale, Gross Unrealized Losses | 0 | (222)
Debt Securities, Available-for-Sale, Fair Value | 10,007 | 9,736
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 128,260 | 129,267
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 1,532 | 68
Debt Securities, Available-for-Sale, Gross Unrealized Losses | (19) | (1,074)
Debt Securities, Available-for-Sale, Fair Value | 129,773 | 128,261
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 147,692 | 149,849
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 3,029 | 795
Debt Securities, Available-for-Sale, Gross Unrealized Losses | (316) | (1,985)
Debt Securities, Available-for-Sale, Fair Value | 150,405 | 148,659
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 20,704 | 24,564
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 289 | 203
Debt Securities, Available-for-Sale, Gross Unrealized Losses | (57) | (417)
Debt Securities, Available-for-Sale, Fair Value | 20,936 | 24,350
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 232,657 | 251,660
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 2,807 | 0
Debt Securities, Available-for-Sale, Gross Unrealized Losses | (172) | (4,876)
Debt Securities, Available-for-Sale, Fair Value | 235,292 | 246,784
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 113,508 | 119,872
Debt Securities, Available-for-Sale, Gross Unrealized Gains | 4,116 | 2,448
Debt Securities, Available-for-Sale, Gross Unrealized Losses | 0 | (54)
Debt Securities, Available-for-Sale, Fair Value | $ 117,624 | $ 122,266

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