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Subordinated Debentures Held by Subsidiary Trusts (Details) $ in Millions | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2023 USD ($) trusts | Dec. 31, 2022 USD ($) | May 31, 2020 | Nov. 01, 2007 | Jun. 22, 2005
Subordinated Borrowing |  |  |  |  |
Number of company sponsored wholly-owned business trusts | trusts | 14 |  |  |  |
Stated interest rate |  |  | 5.25% |  |
Subordinated Debt | $ 163.7 | $ 163.7 |  |  |
Subordinated Long-term Debt, Noncurrent |  | 163.1 |  |  |
Common Stock Held in Assets | 5.3 | 5.3 |  |  |
Subordinated Debt Fair Value Adjustment | (0.6) | (0.6) |  |  |
Subordinated debentures held by subsidiary trusts | 163.1 | 163.1 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 2.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 5.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 30.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 22.4 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC III |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 5.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 7.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC V |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 5.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | 2.0 |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | 0.1 | 0.1 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 2.1 | 2.1 |  |  |
Debt instrument, basis spread on variable rate | 1.85% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust II | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.50% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST II |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.3 | 0.3 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST II | Junior Subordinated Deferrable Interest Debentures Issued by FIST II |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 10.3 | 10.3 |  |  |
Debt instrument, basis spread on variable rate | 2.25% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST II | Junior Subordinated Deferrable Interest Debentures Issued by FIST II | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.91% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST I |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.5 | 0.5 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Junior Subordinated Deferrable Interest Debentures Issued by FIST I |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 15.5 | 15.5 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.40% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Debt Instrument, Redemption, After Period Five |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, basis spread on variable rate | 2.75% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Junior Subordinated Deferrable Interest Debentures Issued by FIST I | Debt Instrument, Redemption, At Issuance through Year Five [Member] |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Stated interest rate |  |  |  | 7.50% |
Junior Subordinated Deferrable Interest Debentures Issued by FIST III |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.6 | 0.6 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Junior Subordinated Deferrable Interest Debentures Issued by FIST III |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 20.6 | 20.6 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.05% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Debt Instrument, Redemption, After Period Five |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, basis spread on variable rate | 2.40% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Junior Subordinated Deferrable Interest Debentures Issued by FIST III | Debt Instrument, Redemption, At Issuance through Year Five [Member] |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Stated interest rate |  |  |  |  | 6.88%
Junior Subordinated Deferrable Interest Debentures Issued by FIST IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.5 | 0.5 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST IV | Junior Subordinated Deferrable Interest Debentures Issued by FIST IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 15.5 | 15.5 |  |  |
Debt instrument, basis spread on variable rate | 2.70% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST IV | Junior Subordinated Deferrable Interest Debentures Issued by FIST IV | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.36% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST V |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.3 | 0.3 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Junior Subordinated Deferrable Interest Debentures Issued by FIST V |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 10.3 | 10.3 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.41% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Debt Instrument, Redemption, After Period Five |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, basis spread on variable rate | 2.75% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Junior Subordinated Deferrable Interest Debentures Issued by FIST V | Debt Instrument, Redemption, At Issuance through Year Five [Member] |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Stated interest rate |  |  |  |  | 6.78%
Junior Subordinated Deferrable Interest Debentures Issued by FIST VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.3 | 0.3 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST VI | Junior Subordinated Deferrable Interest Debentures Issued by FIST VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 10.3 | 10.3 |  |  |
Debt instrument, basis spread on variable rate | 2.75% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by FIST VI | Junior Subordinated Deferrable Interest Debentures Issued by FIST VI | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.41% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.2 | 0.2 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 5.2 | 5.2 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.29% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Debt Instrument, Redemption, After Period Five |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.70% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Junior Subordinated Deferrable Interest Debentures Issued by INB Cap Trust I | Debt Instrument, Redemption, At Issuance through Year Five [Member] |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Stated interest rate |  |  |  |  | 5.95%
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.9 | 0.9 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 30.9 | 30.9 |  |  |
Debt instrument, basis spread on variable rate | 1.48% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust VI | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.13% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.7 | 0.7 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 23.1 | 23.1 |  |  |
Debt instrument, basis spread on variable rate | 2.85% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV | Junior Subordinated Deferrable Interest Debentures Issued by GWB Trust IV | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.49% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC III |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.2 | 0.2 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC III | Junior Subordinated Deferrable Interest Debentures Issued by HFFC III |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 5.2 | 5.2 |  |  |
Debt instrument, basis spread on variable rate | 3.35% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC III | Junior Subordinated Deferrable Interest Debentures Issued by HFFC III | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 9.01% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.2 | 0.2 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV | Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 7.2 | 7.2 |  |  |
Debt instrument, basis spread on variable rate | 3.10% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV | Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 8.76% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC V |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.3 | 0.3 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC V | Junior Subordinated Deferrable Interest Debentures Issued by HFFC V |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 5.3 | 5.3 |  |  |
Debt instrument, basis spread on variable rate | 1.83% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC V | Junior Subordinated Deferrable Interest Debentures Issued by HFFC V | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.47% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Common Stock Held in Assets | $ 0.2 | 0.2 |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI | Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Subordinated Debt | $ 2.2 | $ 2.2 |  |  |
Debt instrument, basis spread on variable rate | 1.65% |  |  |  |
Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI | Junior Subordinated Deferrable Interest Debentures Issued by HFFC VI | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Debt instrument, interest rate at period end | 7.31% |  |  |  |
Trust Preferred Securities Subject to Mandatory Redemption | Trusts |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Business trust term (in years) | 30 years |  |  |  |
Common Stock Subject to Mandatory Redemption | Trusts |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Amount of financial instruments subject to mandatory redemption | $ 5.3 |  |  |  |
Subordinated Debentures Subject to Mandatory Redemption | Trusts |  |  |  |  |
Subordinated Borrowing |  |  |  |  |
Business trust term (in years) | 30 years |  |  |  |

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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482900/835-30-50-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482925/835-30-45-2 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-6 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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- Definition Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481372/852-10-55-10 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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