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Investment Securities - Additional Information (Details) | 9 Months Ended | 12 Months Ended
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Sep. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
Investments Debt And Equity Securities [Abstract] |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 9 | 69
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 8 | 35
Other than temporary impairment loss debt securities available for sale interest rate | 1.50% |
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Total | $ 0 | $ 0
Debt Securities, Available-for-sale, Restricted | $ 73,800,000 | $ 51,700,000

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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455 + Details
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455 + Details
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- Definition Amount of restricted 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 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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