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Securities - Unrealized Loss Positions (Details) | Sep. 30, 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 | 15 | 16
Greater than 12 months in an unrealized loss position | security | 16 | 61
Total | 31 | 77
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 534,000 | $ 1,256,000
Greater than 12 months in an unrealized loss position | 1,015,000 | 7,592,000
Total | 1,549,000 | 8,848,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 84,211,000 | 86,856,000
Greater than 12 months in an unrealized loss position | 47,323,000 | 197,238,000
Total | $ 131,534,000 | $ 284,094,000
US Treasury Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Greater than 12 months in an unrealized loss position | security |  | 1
Total |  | 1
Securities Available-for-Sale, Unrealized Losses |  |
Greater than 12 months in an unrealized loss position |  | $ 83,000
Total |  | 83,000
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position |  | 3,923,000
Total |  | $ 3,923,000
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 | 4 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | $ 100,000
Greater than 12 months in an unrealized loss position | $ 161,000 | 61,000
Total | 161,000 | 161,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position |  | 7,385,000
Greater than 12 months in an unrealized loss position | 9,143,000 | 3,566,000
Total | $ 9,143,000 | $ 10,951,000
Mortgage Backed Securities, Issued by US Government Agencies [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 | 2 | 11
Total | 5 | 11
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 7,000 |
Greater than 12 months in an unrealized loss position | 10,000 | $ 377,000
Total | 17,000 | 377,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 3,044,000 |
Greater than 12 months in an unrealized loss position | 848,000 | 11,439,000
Total | $ 3,892,000 | $ 11,439,000
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 | 3 | 4
Greater than 12 months in an unrealized loss position | security | 2 | 33
Total | 5 | 37
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 326,000 | $ 126,000
Greater than 12 months in an unrealized loss position | 589,000 | 4,835,000
Total | 915,000 | 4,961,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 15,526,000 | 17,713,000
Greater than 12 months in an unrealized loss position | 6,757,000 | 110,326,000
Total | $ 22,283,000 | $ 128,039,000
Collateralized Mortgage Obligations [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 2 | 2
Greater than 12 months in an unrealized loss position | security | 3 | 10
Total | 5 | 12
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 44,000 | $ 309,000
Greater than 12 months in an unrealized loss position | 16,000 | 1,835,000
Total | 60,000 | 2,144,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 9,320,000 | 15,211,000
Greater than 12 months in an unrealized loss position | 2,332,000 | 43,687,000
Total | $ 11,652,000 | $ 58,898,000
Asset-backed Securities [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 | 1 | 4
Total | 3 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 101,000 |
Greater than 12 months in an unrealized loss position | 66,000 | $ 225,000
Total | 167,000 | 225,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 29,389,000 |
Greater than 12 months in an unrealized loss position | 3,213,000 | 16,473,000
Total | $ 32,602,000 | $ 16,473,000
Collateralized loan obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 5 | 7
Greater than 12 months in an unrealized loss position | security | 4 | 1
Total | 9 | 8
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 56,000 | $ 721,000
Greater than 12 months in an unrealized loss position | 173,000 | 176,000
Total | 229,000 | 897,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 26,932,000 | 46,547,000
Greater than 12 months in an unrealized loss position | 25,030,000 | 7,824,000
Total | $ 51,962,000 | $ 54,371,000

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