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Securities (Details Textual)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($)	Jun. 30, 2020	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Available-for-sale securities, gross realized gain (loss)	$ 0	$ 98,000		$ 0	$ 139,000
Gross gains resulting from sale of available-for-sale securities	100,000			100,000
Continuous unrealized loss position, fair value	$ 462,400,000			$ 462,400,000		$ 226,500,000
Continuous unrealized loss position, fair value (as a percent)			40.00%	66.00%
Number of securities in portfolio | security	441			441
Securities in unrealized loss position | security	167			167

X

- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position in percentage.

+ References

No definition available.

+ Details

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- Definition

Debt Securities, Number Of Securities In Portfolio

+ References

No definition available.

+ Details

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- Definition

Debt Securities, Unrealized Loss Position, Number Of Positions

+ References

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- Definition

Securities, Continuous Unrealized Loss Position, Fair Value

+ References

No definition available.

+ Details

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- Definition

Amount of realized gain on 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 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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- Definition

Amount of realized gain (loss) on 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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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- References

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