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Securities - Unrealized Loss Positions (Details) $ in Thousands | Mar. 31, 2018 USD ($) security | Dec. 31, 2017 USD ($) security
--- | --- | ---
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 61 | 26
Greater than 12 months in an unrealized loss position | security | 22 | 22
Total | security | 83 | 48
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 3,667 | $ 1,457
Greater than 12 months in an unrealized loss position | 5,120 | 3,216
Total | 8,787 | 4,673
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 201,552 | 102,830
Greater than 12 months in an unrealized loss position | 103,630 | 108,651
Total | $ 305,182 | $ 211,481
U.S. Treasury |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 1 | 1
Total | security | 1 | 1
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 108 | $ 55
Total | 108 | 55
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 3,895 | 3,947
Total | $ 3,895 | $ 3,947
U.S. government agencies |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 2
Total | security | 4 | 2
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 58 | $ 9
Total | 58 | 9
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 12,730 | 6,550
Total | $ 12,730 | $ 6,550
U.S. government agency mortgage-backed |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 7 | 4
Greater than 12 months in an unrealized loss position | security | 5 | 5
Total | security | 12 | 9
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 254 | $ 24
Greater than 12 months in an unrealized loss position | 233 | 141
Total | 487 | 165
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 9,130 | 5,501
Greater than 12 months in an unrealized loss position | 4,714 | 4,843
Total | $ 13,844 | $ 10,344
States and political subdivisions |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 42 | 13
Greater than 12 months in an unrealized loss position | security | 2 | 1
Total | security | 44 | 14
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 3,068 | $ 1,237
Greater than 12 months in an unrealized loss position | 1,263 | 27
Total | 4,331 | 1,264
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 140,012 | 45,985
Greater than 12 months in an unrealized loss position | 3,742 | 1,512
Total | $ 143,754 | $ 47,497
Corporate bonds |  |
Securities Available-for-Sale, Number of Securities |  |
Greater than 12 months in an unrealized loss position | security | 1 | 1
Total | security | 1 | 1
Securities Available-for-Sale, Unrealized Losses |  |
Greater than 12 months in an unrealized loss position | $ 5 | $ 11
Total | 5 | 11
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position | 200 | 332
Total | $ 200 | $ 332
Collateralized mortgage obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 3
Greater than 12 months in an unrealized loss position | security | 8 | 8
Total | security | 12 | 11
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 110 | $ 31
Greater than 12 months in an unrealized loss position | 1,778 | 1,124
Total | 1,888 | 1,155
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 21,191 | 11,534
Greater than 12 months in an unrealized loss position | 38,589 | 40,219
Total | $ 59,780 | $ 51,753
Asset-backed securities |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 1 |
Greater than 12 months in an unrealized loss position | security | 6 | 7
Total | security | 7 | 7
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 46 |
Greater than 12 months in an unrealized loss position | 1,841 | $ 1,913
Total | 1,887 | 1,913
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 1,603 |
Greater than 12 months in an unrealized loss position | 56,385 | 61,745
Total | $ 57,988 | $ 61,745
Collateralized loan obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 2 | 3
Total | security | 2 | 3
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 23 | $ 101
Total | 23 | 101
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 12,991 | 29,313
Total | $ 12,991 | $ 29,313

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