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Summary of Significant Accounting Policies - Financing Receivable Narrative (Details)	12 Months Ended
	Dec. 31, 2020 payment
Accounting Policies [Abstract]
Threshold period a past due loan is charged off	90 days
Number of consecutive payments considered sustained repayment performance	6
Threshold period a past due overdraft account is charged off	60 days

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- Definition

Loans and Leases Receivable, Nonperforming, Number Of Consecutive Payments Considered Sustained Repayment Performance

+ References

No definition available.

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- Definition

Threshold Period Past Due For Write-Off Of Deposit Liabilities Reclassified As Loans Receivable

+ References

No definition available.

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- References

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- Definition

Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919253-210447

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