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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% |  |  |  |

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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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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- 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 + Details
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