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Fair Value - Additional Information (Details) - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Fair Value Disclosures [Abstract] |  |  |
Mortgage servicing rights impairment | $ 91,000 | $ 258,000 | $ 358,000
Other real estate owned, valuation allowance | 0 | 45,000 | 45,000
Valuation allowance on impaired financing receivable | $ 457,000 | $ 633,000 | $ 304,000

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- Definition Impaired Financing Receivable Measured At Fair Value, Related Allowance + References No definition available. + Details
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- References No definition available. + Details
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- Definition For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122739-111746 + Details
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