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Securities - Unrealized Loss Positions (Details) | Sep. 30, 2020 USD ($) security | Dec. 31, 2019 USD ($) security
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Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 11 | 19
Greater than 12 months in an unrealized loss position | security | 13 | 15
Total | 24 | 34
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 971,000 | $ 2,602,000
Greater than 12 months in an unrealized loss position | 2,412,000 | 1,181,000
Total | 3,383,000 | 3,783,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 38,266,000 | 129,582,000
Greater than 12 months in an unrealized loss position | 65,470,000 | 45,240,000
Total | $ 103,736,000 | $ 174,822,000
US Government Corporations and Agencies Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Greater than 12 months in an unrealized loss position | security | 4 | 4
Total | 4 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Greater than 12 months in an unrealized loss position | $ 164,000 | $ 165,000
Total | 164,000 | 165,000
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position | 7,005,000 | 8,337,000
Total | $ 7,005,000 | $ 8,337,000
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 | 1 | 3
Greater than 12 months in an unrealized loss position | security |  | 2
Total | 1 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 2,000 | $ 10,000
Greater than 12 months in an unrealized loss position |  | 9,000
Total | 2,000 | 19,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 260,000 | 3,018,000
Greater than 12 months in an unrealized loss position |  | 843,000
Total | $ 260,000 | $ 3,861,000
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 |  | 6
Greater than 12 months in an unrealized loss position | security | 1 | 2
Total | 1 | 8
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position |  | $ 1,665,000
Greater than 12 months in an unrealized loss position | $ 955,000 | 766,000
Total | 955,000 | 2,431,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position |  | 41,043,000
Greater than 12 months in an unrealized loss position | 3,872,000 | 6,593,000
Total | $ 3,872,000 | $ 47,636,000
Collateralized Mortgage Obligations [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 4 | 2
Greater than 12 months in an unrealized loss position | security | 1 | 2
Total | 5 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 421,000 | $ 26,000
Greater than 12 months in an unrealized loss position | 2,000 | 12,000
Total | 423,000 | 38,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 8,027,000 | 9,054,000
Greater than 12 months in an unrealized loss position | 279,000 | 1,209,000
Total | $ 8,306,000 | $ 10,263,000
Asset-backed Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 5 | 4
Greater than 12 months in an unrealized loss position | security | 3 | 1
Total | 8 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 425,000 | $ 839,000
Greater than 12 months in an unrealized loss position | 881,000 | 48,000
Total | 1,306,000 | 887,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 22,603,000 | 54,540,000
Greater than 12 months in an unrealized loss position | 33,069,000 | 3,238,000
Total | $ 55,672,000 | $ 57,778,000
Collateralized loan obligations |  |
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 | 4 | 4
Total | 5 | 8
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 123,000 | $ 62,000
Greater than 12 months in an unrealized loss position | 410,000 | 181,000
Total | 533,000 | 243,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 7,376,000 | 21,927,000
Greater than 12 months in an unrealized loss position | 21,245,000 | 25,020,000
Total | $ 28,621,000 | $ 46,947,000

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