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Loans - Additional Information (Details) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 USD ($) loan_portfolio | Dec. 31, 2020 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Number of loan portfolios | loan_portfolio | 4 |
Off-balance sheet, credit loss, liability | $ 1.8 |
Cumulative Effect, Period of Adoption, Adjusted Balance |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Off-balance sheet, credit loss, liability |  | $ 1.1
Consumer | Minimum | Automobile Loan |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Principal repayment terms, period | 3 years |
Consumer | Minimum | Credit Card Receivable |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Principal repayment terms, period | 1 year |
Consumer | Maximum | Automobile Loan |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Principal repayment terms, period | 7 years |
Consumer | Maximum | Credit Card Receivable |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Principal repayment terms, period | 5 years |

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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. 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 460 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82919202-210446 + Details
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