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Securities - Unrealized Loss Positions (Details) | Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($)
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Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | 7 | 19
Greater than 12 months in an unrealized loss position | 13 | 15
Total | 20 | 34
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 313,000 | $ 2,602,000
Greater than 12 months in an unrealized loss position | 2,205,000 | 1,181,000
Total | 2,518,000 | 3,783,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 16,002,000 | 129,582,000
Greater than 12 months in an unrealized loss position | 81,285,000 | 45,240,000
Total | $ 97,287,000 | $ 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 | 4 | 4
Total | 4 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Greater than 12 months in an unrealized loss position | $ 154,000 | $ 165,000
Total | 154,000 | 165,000
Securities Available-for-Sale, Fair Value |  |
Greater than 12 months in an unrealized loss position | 6,657,000 | 8,337,000
Total | $ 6,657,000 | $ 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 | 1 | 3
Greater than 12 months in an unrealized loss position |  | 2
Total | 1 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 1,000 | $ 10,000
Greater than 12 months in an unrealized loss position |  | 9,000
Total | 1,000 | 19,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 141,000 | 3,018,000
Greater than 12 months in an unrealized loss position |  | 843,000
Total | $ 141,000 | $ 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 |  | 6
Greater than 12 months in an unrealized loss position | 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 | $ 1,362,000 | 766,000
Total | 1,362,000 | 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 | 3,433,000 | 6,593,000
Total | $ 3,433,000 | $ 47,636,000
Collateralized Mortgage Obligations [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | 4 | 2
Greater than 12 months in an unrealized loss position | 1 | 2
Total | 5 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 279,000 | $ 26,000
Greater than 12 months in an unrealized loss position | 1,000 | 12,000
Total | 280,000 | 38,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 8,142,000 | 9,054,000
Greater than 12 months in an unrealized loss position | 146,000 | 1,209,000
Total | $ 8,288,000 | $ 10,263,000
Asset-backed Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | 1 | 4
Greater than 12 months in an unrealized loss position | 3 | 1
Total | 4 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 2,000 | $ 839,000
Greater than 12 months in an unrealized loss position | 509,000 | 48,000
Total | 511,000 | 887,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 251,000 | 54,540,000
Greater than 12 months in an unrealized loss position | 49,572,000 | 3,238,000
Total | $ 49,823,000 | $ 57,778,000
Collateralized loan obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | 1 | 4
Greater than 12 months in an unrealized loss position | 4 | 4
Total | 5 | 8
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 31,000 | $ 62,000
Greater than 12 months in an unrealized loss position | 179,000 | 181,000
Total | 210,000 | 243,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 7,468,000 | 21,927,000
Greater than 12 months in an unrealized loss position | 21,477,000 | 25,020,000
Total | $ 28,945,000 | $ 46,947,000

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