Federal Income Taxes - Schedule of Total Federal Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Taxes (benefits) on earnings from continuing operations:
Current	$ 15,830	$ 42,829	$ (275)
Deferred	9,060	3,747	20,031
Taxes on earnings from continuing operations	24,890	46,576	19,756
Taxes (benefits) on components of stockholders' equity:	(168,094)	(47,706)	89,135
Total Federal income taxes	(143,203)	(1,131)	108,084
Net unrealized gains and losses on securities available-for-sale
Taxes (benefits) on earnings from continuing operations:
Taxes (benefits) on components of stockholders' equity:	(171,770)	(51,177)	92,528
Foreign currency translation adjustments
Taxes (benefits) on earnings from continuing operations:
Taxes (benefits) on components of stockholders' equity:	108	(4)	4
Change in benefit plan liability
Taxes (benefits) on earnings from continuing operations:
Taxes (benefits) on components of stockholders' equity:	3,569	3,474	(3,398)
Change in accounting
Taxes (benefits) on earnings from continuing operations:
Taxes (benefits) on components of stockholders' equity:	$ 0	$ 0	$ (806)