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Securities (Details Textual) | 3 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) security | Sep. 30, 2020 USD ($) | Jun. 30, 2020 | Sep. 30, 2021 USD ($) security | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |  |
Available-for-sale securities, gross realized gain (loss) | $ 0 | $ 98,000 |  | $ 0 | $ 139,000 |
Gross gains resulting from sale of available-for-sale securities | 100,000 |  |  | 100,000 |  |
Continuous unrealized loss position, fair value | $ 462,400,000 |  |  | $ 462,400,000 |  | $ 226,500,000
Continuous unrealized loss position, fair value (as a percent) |  |  | 40.00% | 66.00% |  |
Number of securities in portfolio | security | 441 |  |  | 441 |  |
Securities in unrealized loss position | security | 167 |  |  | 167 |  |

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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=121645371&loc=d3e27357-111563 + Details
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