CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 191,054	$ 249,268	$ 345,601	$ 424,281
Other comprehensive income (loss), net of tax:
Change in unrealized investment gains and losses	(30,234)	(175,380)	50,425	(446,318)
Benefit plan adjustments	846	490	6,199	883
Other comprehensive income (loss), net of tax	(29,388)	(174,890)	56,624	(445,435)
Comprehensive income (loss)	$ 161,666	$ 74,378	$ 402,225	$ (21,154)