Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 3,704,307	$ 3,607,085	$ 1,465,534	$ 1,500,627	$ 3,607,085	$ 1,500,627
Other comprehensive income (loss), net	41	(2,186)	(1,163)	(424)	(2,145)	(1,587)
Ending balance	3,719,420	3,704,307	1,508,794	1,465,534	3,719,420	1,508,794
Defined Benefit Pension Items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	1,461	3,647	4,965	5,389	3,647	5,389
Other comprehensive income (loss) before reclassifications	41	(2,186)	(1,163)	(424)
Amounts reclassified from AOCI	0	0	0	0
Other comprehensive income (loss), net	41	(2,186)	(1,163)	(424)
Ending balance	$ 1,502	$ 1,461	$ 3,802	$ 4,965	$ 1,502	$ 3,802