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Subordinated Debt (Details Textual) - Subordinated Debt - USD ($)	1 Months Ended			9 Months Ended
	Aug. 31, 2021	Oct. 31, 2020	Jun. 30, 2019	Sep. 30, 2021	Oct. 20, 2015
2025 Note
Debt Instrument [Line Items]
Subordinated debenture, principal amount					$ 10,000,000
Fixed annual interest rate (as a percent)					6.4375%
2026 Notes
Debt Instrument [Line Items]
Subordinated debenture, principal amount				$ 25,000,000
Fixed annual interest rate (as a percent)				6.00%
2029 Notes
Debt Instrument [Line Items]
Subordinated debenture, principal amount				$ 37,000,000
Fixed annual interest rate (as a percent)				6.00%
2030 Notes
Debt Instrument [Line Items]
Subordinated debenture, principal amount		$ 10,000,000
Fixed annual interest rate (as a percent)		6.00%
2031 Notes
Debt Instrument [Line Items]
Subordinated debenture, principal amount	$ 60,000,000
Fixed annual interest rate (as a percent)	3.75%
LIBOR | 2026 Notes
Debt Instrument [Line Items]
Basis spread on variable rate				485.00%
LIBOR | 2029 Notes
Debt Instrument [Line Items]
Basis spread on variable rate			411.00%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | 2030 Notes
Debt Instrument [Line Items]
Basis spread on variable rate		5.795%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | 2031 Notes
Debt Instrument [Line Items]
Basis spread on variable rate	3.11%

X

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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