Basis of Accounting and Consolidation - Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Realized gains on available-for-sale securities	$ 73	$ 287	$ 77	$ 818
Tax effect	(3,357)	(3,096)	(4,025)	(6,268)
Total reclassifications out of accumulated other comprehensive income	52	204	55	581
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Realized gains on available-for-sale securities	73	287	77	818
Tax effect	$ (21)	$ (83)	$ (22)	$ (237)