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Investment Securities - Narrative (Details) | Sep. 30, 2021 USD ($) security | Dec. 31, 2020 USD ($) security
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Investments, Debt and Equity Securities [Abstract] |  |
Held-to-maturity, allowance for credit Loss | $ | $ 0 | $ 0
Number of investment securities in unrealized loss position | 165 | 10
Number of investment securities in unrealized loss position longer than 12 months | 6 |
Number of investment securities in unrealized loss position less than 12 months | 159 |
Debt securities, available-for-sale unrealized loss position, allowance for credit loss | $ | $ 0 |

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- Definition Debt Securities, Available-For-Sale Unrealized Loss Position, Allowance For Credit Loss + References No definition available. + Details
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- Definition Marketable Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions + References No definition available. + Details
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- Definition Marketable Securities In Unrealized Loss Positions, Qualitative Disclosure, Number Of Positions, Less Than 12 Months + References No definition available. + Details
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- Definition Marketable Securities In Unrealized Loss Positions, Qualitative Disclosure, Number Of Positions, Longer Than 12 Months + References No definition available. + Details
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- Definition Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
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- References No definition available. + Details
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