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Securities - Unrealized Loss Positions (Details) $ in Thousands | Mar. 31, 2019 USD ($) security | Dec. 31, 2018 USD ($) security
--- | --- | ---
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 9 | 16
Greater than 12 months in an unrealized loss position | security | 41 | 61
Total | security | 50 | 77
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 206 | $ 1,256
Greater than 12 months in an unrealized loss position | 4,325 | 7,592
Total | 4,531 | 8,848
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 56,863 | 86,856
Greater than 12 months in an unrealized loss position | 148,615 | 197,238
Total | $ 205,478 | $ 284,094
US Treasury Securities [Member] |  |
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 | $ 47 | $ 83
Total | 47 | 83
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position | 3,960 | 3,923
Total | $ 3,960 | $ 3,923
US Government Corporations and Agencies Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security |  | 3
Greater than 12 months in an unrealized loss position | security | 4 | 1
Total | security | 4 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | $ 100
Greater than 12 months in an unrealized loss position | $ 151 | 61
Total | 151 | 161
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position |  | 7,385
Greater than 12 months in an unrealized loss position | 10,360 | 3,566
Total | $ 10,360 | $ 10,951
Mortgage Backed Securities, Issued by US Government Agencies [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Greater than 12 months in an unrealized loss position | security | 10 | 11
Total | security | 10 | 11
Securities Available-for-Sale, Unrealized Losses |  |
Greater than 12 months in an unrealized loss position | $ 154 | $ 377
Total | 154 | 377
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position | 9,575 | 11,439
Total | $ 9,575 | $ 11,439
US States and Political Subdivisions Debt Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 4
Greater than 12 months in an unrealized loss position | security | 9 | 33
Total | security | 13 | 37
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 1 | $ 126
Greater than 12 months in an unrealized loss position | 2,086 | 4,835
Total | 2,087 | 4,961
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 808 | 17,713
Greater than 12 months in an unrealized loss position | 41,500 | 110,326
Total | $ 42,308 | $ 128,039
Collateralized Mortgage Obligations [Member] |  |
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 | 11 | 10
Total | security | 11 | 12
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | $ 309
Greater than 12 months in an unrealized loss position | $ 1,206 | 1,835
Total | 1,206 | 2,144
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position |  | 15,211
Greater than 12 months in an unrealized loss position | 53,431 | 43,687
Total | $ 53,431 | $ 58,898
Asset-backed Securities [Member] |  |
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 | 2 | 4
Total | security | 3 | 4
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 | 104 | $ 225
Total | 150 | 225
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 27,731 |
Greater than 12 months in an unrealized loss position | 4,952 | 16,473
Total | $ 32,683 | $ 16,473
Collateralized loan obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 7
Greater than 12 months in an unrealized loss position | security | 4 | 1
Total | security | 8 | 8
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 159 | $ 721
Greater than 12 months in an unrealized loss position | 577 | 176
Total | 736 | 897
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 28,324 | 46,547
Greater than 12 months in an unrealized loss position | 24,837 | 7,824
Total | $ 53,161 | $ 54,371

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