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Securities (Details Textual) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Debt Securities, Available-for-sale, Realized Gain | $ 5 | $ 5 |  |
Cumulative OTTI charges | $ 2,974 | $ 2,974 | $ 2,974 | $ 2,974
Minimum [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Basis point spread on variable rate | 1.60% |  |  |
Maximum [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Basis point spread on variable rate | 1.80% |  |  |

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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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