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Securities - Fair Values of Marketable Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Investments, Debt and Equity Securities [Abstract] |  |
Debt securities, available-for-sale, excluding accrued interest | $ 868,994 | $ 770,393
Marketable equity securities | 1,127 | 3,300
Total Securities | $ 870,121 | $ 773,693

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- Definition Debt Securities, Available-for-sale and Equity Securities, FV-NI + References No definition available. + Details
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- Definition Amount excluding accrued interest, of 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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 + Details
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