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Junior Subordinated Interest Deferrable Debentures (Key Information) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Junior subordinated interest deferrable debentures, major types of business trusts
Junior subordinated deferrable interest debentures	$ 108,868,000	$ 134,642,000
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)	6.80%
Interest rate index	LIBOR
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)	6.95%
Interest rate index	LIBOR
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)	6.80%
Interest rate index	LIBOR
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)	6.95%
Interest rate index	LIBOR
Spread on interest rate index (as a percent)	1.45%

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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