Basis of Accounting and Consolidation - Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Realized gain (loss) on available-for-sale securities	$ 3,389	$ 79	$ 3,337	$ 81
Tax effect	(5,372)	(5,418)	(15,888)	(15,277)
Total reclassifications out of accumulated other comprehensive income (loss)	2,406	56	2,369	57
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Realized gain (loss) on available-for-sale securities	3,389	79	3,337	81
Tax effect	$ (983)	$ (23)	$ (968)	$ (24)