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Securities - Other securities policy (Details)	Dec. 31, 2020 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of Pooled Trust Preferred Securities	2
Fair Value of Pooled Trust Preferred Securities Held	$ 680,000
Unrealized Losses on Pooled Trust Preferred Securities in a Continuous Unrealized Loss Position for 12 Months or More	$ 296,000
Prepayments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	0.016
Annual defaults
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	0.0050
Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input rate	0.10
Lagged years
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, Input term	2 years

X

- Definition

Represents the monetary amount of Fair Value of Pooled Trust Preferred Securities Held, as of the indicated date.

+ References

No definition available.

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- Definition

Represents the pure numeric value of Number of Pooled Trust Preferred Securities, as of the indicated date.

+ References

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- Definition

Represents the monetary amount of Unrealized Losses on Pooled Trust Preferred Securities in a Continuous Unrealized Loss Position for 12 Months or More, as of the indicated date.

+ References

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- Definition

Value of input used to measure 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

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