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Securities - Unrealized Loss Positions (Details) | 3 Months Ended |
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Sep. 30, 2021 USD ($) security | Dec. 31, 2020 USD ($) security
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 29 | 7
Greater than 12 months in an unrealized loss position | security | 9 | 13
Total | 38 | 20
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 825,000 | $ 313,000
Greater than 12 months in an unrealized loss position | 892,000 | 2,205,000
Total | 1,717,000 | 2,518,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 159,561,000 | 16,002,000
Greater than 12 months in an unrealized loss position | 31,020,000 | 81,285,000
Total | 190,581,000 | $ 97,287,000
Credit losses were determined | 0 |
Provision for credit losses on securities | $ 0 |
US Government Corporations and Agencies 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 | 4 | 4
Total | 6 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 229,000 |
Greater than 12 months in an unrealized loss position | 111,000 | $ 154,000
Total | 340,000 | 154,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 28,066,000 |
Greater than 12 months in an unrealized loss position | 5,509,000 | 6,657,000
Total | $ 33,575,000 | $ 6,657,000
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 | 6 | 1
Total | 6 | 1
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 215,000 | $ 1,000
Total | 215,000 | 1,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 6,084,000 | 141,000
Total | $ 6,084,000 | $ 141,000
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 | 2 |
Greater than 12 months in an unrealized loss position | security | 1 | 1
Total | 3 | 1
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 23,000 |
Greater than 12 months in an unrealized loss position | 616,000 | $ 1,362,000
Total | 639,000 | 1,362,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 1,490,000 |
Greater than 12 months in an unrealized loss position | 4,085,000 | 3,433,000
Total | $ 5,575,000 | $ 3,433,000
Corporate Bond Securities [Member] |  |
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 | $ 8,000 |
Total | 8,000 |
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 4,992,000 |
Total | $ 4,992,000 |
Collateralized Mortgage Obligations [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 7 | 4
Greater than 12 months in an unrealized loss position | security | 1 | 1
Total | 8 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 244,000 | $ 279,000
Greater than 12 months in an unrealized loss position | 64,000 | 1,000
Total | 308,000 | 280,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 63,495,000 | 8,142,000
Greater than 12 months in an unrealized loss position | 7,531,000 | 146,000
Total | $ 71,026,000 | $ 8,288,000
Asset-backed Securities [Member] |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 5 | 1
Greater than 12 months in an unrealized loss position | security | 1 | 3
Total | 6 | 4
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 79,000 | $ 2,000
Greater than 12 months in an unrealized loss position | 54,000 | 509,000
Total | 133,000 | 511,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 35,048,000 | 251,000
Greater than 12 months in an unrealized loss position | 3,270,000 | 49,572,000
Total | $ 38,318,000 | $ 49,823,000
Collateralized loan obligations |  |
Securities Available-for-Sale, Number of Securities |  |
Less than 12 months in an unrealized loss position | security | 6 | 1
Greater than 12 months in an unrealized loss position | security | 2 | 4
Total | 8 | 5
Securities Available-for-Sale, Unrealized Losses |  |
Less than 12 months in an unrealized loss position | $ 27,000 | $ 31,000
Greater than 12 months in an unrealized loss position | 47,000 | 179,000
Total | 74,000 | 210,000
Securities Available-for-Sale, Fair Value |  |
Less than 12 months in an unrealized loss position | 20,386,000 | 7,468,000
Greater than 12 months in an unrealized loss position | 10,625,000 | 21,477,000
Total | $ 31,011,000 | $ 28,945,000

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