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Disclosures About Offsetting Assets And Liabilities (Financial Liabilities And Derivative Liabilities That Are Subject To Offset) (Details) (Parenthetical) - USD ($) $ in Thousands | Sep. 30, 2021 | Jun. 30, 2021 | Dec. 31, 2020
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Offsetting Liabilities [Line Items] |  |  |
Fair value of securities pledged as collateral to counter party | $ 184,796 |  | $ 172,963
U.S. Government Agency Securities And U.S. Government Securities And Corporate Fixed Income Securities [Member] | Fair Value Of Securities Pledged As Collateral [Member] |  |  |
Offsetting Liabilities [Line Items] |  |  |
Fair value of securities pledged as collateral to counter party |  | $ 200,600 | $ 200,200

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- Definition Fair value of securities pledged as collateral against securities sold under agreement to repurchase. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313 + Details
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