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Junior Subordinated Interest Deferrable Debentures - Key Information (Details) - USD ($) |  | 6 Months Ended |
--- | --- | --- | ---
Jul. 01, 2023 | Jun. 30, 2024 | Dec. 31, 2023
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Junior subordinated deferrable interest debentures |  | $ 108,868,000 | $ 108,868,000
Trust IX |  |  |
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Junior subordinated deferrable interest debentures |  | $ 41,238,000 |
Interest rate (as a percent) |  | 7.18% |
Interest rate index |  | SOFR |
Spread on interest rate index (as a percent) |  | 1.62% |
Trust X |  |  |
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Junior subordinated deferrable interest debentures |  | $ 21,021,000 |
Interest rate (as a percent) |  | 7.24% |
Interest rate index |  | SOFR |
Spread on interest rate index (as a percent) |  | 1.65% |
Trust XI |  |  |
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Junior subordinated deferrable interest debentures |  | $ 25,990,000 |
Interest rate (as a percent) |  | 7.18% |
Interest rate index |  | SOFR |
Spread on interest rate index (as a percent) |  | 1.62% |
Trust XII |  |  |
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Junior subordinated deferrable interest debentures |  | $ 20,619,000 |
Interest rate (as a percent) |  | 7.06% |
Interest rate index |  | SOFR |
Spread on interest rate index (as a percent) |  | 1.45% |
Capital and Common Securities |  |  |
Junior subordinated interest deferrable debentures, major types of business trusts |  |  |
Spread on interest rate index (as a percent) | 0.26% |  |

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