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Fair Value Measurements (Narrative) (Details) - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Material losses related to counterparty's inability to pay undercollateralized position | $ 0 |  |
Significant change in the value of derivative assets and liabilities attributed to credit risk | 0 |  |
Loans individually evaluated |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Provision for loan losses on impaired loans | $ (478,000) |  | $ (1,118,000)
Minimum |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Collateral discount | 10.00% | 10.00% |
Maximum |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Collateral discount | 30.00% | 30.00% |

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- Definition Unobservable Inputs Fair Value Measurement Collateral Discount Percent + References No definition available. + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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