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Securities - Unrealized Loss Positions (Details) $ in Thousands | Sep. 30, 2017 USD ($) security | Dec. 31, 2016 USD ($) security
--- | --- | ---
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 18 | 44
Greater than 12 months in an unrealized loss position | security | 24 | 34
Total | security | 42 | 78
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 1,404 | $ 5,143
Greater than 12 months in an unrealized loss position | 5,052 | 9,463
Total | 6,456 | 14,606
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 71,145 | 216,050
Greater than 12 months in an unrealized loss position | 134,583 | 213,060
Total | $ 205,728 | $ 429,110
U.S. Treasury |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 1 |
Total | security | 1 |
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 11 |
Total | 11 |
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 3,990 |
Total | $ 3,990 |
U.S. government agencies |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 2 | 11
Greater than 12 months in an unrealized loss position | security |  | 1
Total | security | 2 | 12
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 39 | $ 957
Greater than 12 months in an unrealized loss position |  | 20
Total | 39 | 977
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 6,701 | 40,636
Greater than 12 months in an unrealized loss position |  | 898
Total | $ 6,701 | $ 41,534
U.S. government agency mortgage-backed |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 2 |
Greater than 12 months in an unrealized loss position | security | 4 |
Total | security | 6 |
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 13 |
Greater than 12 months in an unrealized loss position | 106 |
Total | 119 |
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 2,089 |
Greater than 12 months in an unrealized loss position | 4,096 |
Total | $ 6,185 |
States and political subdivisions |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 7 | 12
Total | security | 7 | 12
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 789 | $ 273
Total | 789 | 273
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 24,843 | 35,241
Total | $ 24,843 | $ 35,241
Corporate bonds |  |
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 | 3 | 2
Total | security | 3 | 3
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | $ 183
Greater than 12 months in an unrealized loss position | $ 266 | 153
Total | 266 | 336
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position |  | 4,817
Greater than 12 months in an unrealized loss position | 10,078 | 5,328
Total | $ 10,078 | $ 10,145
Collateralized mortgage obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 16
Greater than 12 months in an unrealized loss position | security | 8 | 7
Total | security | 12 | 23
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 238 | $ 3,402
Greater than 12 months in an unrealized loss position | 1,297 | 397
Total | 1,535 | 3,799
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 21,281 | 117,752
Greater than 12 months in an unrealized loss position | 43,684 | 18,109
Total | $ 64,965 | $ 135,861
Asset-backed securities |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 1 | 4
Greater than 12 months in an unrealized loss position | security | 9 | 12
Total | security | 10 | 16
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 265 | $ 328
Greater than 12 months in an unrealized loss position | 3,383 | 7,997
Total | 3,648 | 8,325
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 4,293 | 17,604
Greater than 12 months in an unrealized loss position | 76,725 | 107,112
Total | $ 81,018 | $ 124,716
Collateralized loan obligations |  |
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 |  | 12
Total | security | 1 | 12
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 49 |
Greater than 12 months in an unrealized loss position |  | $ 896
Total | 49 | 896
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 7,948 |
Greater than 12 months in an unrealized loss position |  | 81,613
Total | $ 7,948 | $ 81,613

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