CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 249,625	$ 157,977	$ 673,906	$ 461,049
Other comprehensive income (loss), net of tax:
Change in unrealized investment gains and losses	(153,615)	(27,600)	(599,933)	(76,675)
Benefit plan adjustments	(16,172)	5,963	(15,289)	7,499
Other comprehensive income (loss), net of tax	(169,787)	(21,637)	(615,222)	(69,176)
Comprehensive income (loss)	$ 79,838	$ 136,340	$ 58,684	$ 391,873