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Loans and Allowance for Credit Losses on Loans - Major Classifications - Loan Concentrations (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Real Estate Portfolio Segment [Member] | Loan receivables | Customer Concentration Risk [Member]
Loans
Loans receivable as a percentage of total portfolio	73.40%	72.50%

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- Definition

Represents the percentage of total portfolio that is represented by a particular financial receivable category.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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