CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 249,268	$ 153,051	$ 424,281	$ 303,072
Other comprehensive income (loss), net of tax:
Change in unrealized investment gains and losses	(175,380)	45,054	(446,318)	(49,075)
Benefit plan adjustments	490	663	883	1,536
Other comprehensive income (loss), net of tax	(174,890)	45,717	(445,435)	(47,539)
Comprehensive income (loss)	$ 74,378	$ 198,768	$ (21,154)	$ 255,533