Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pension and Supplemental Executive Retirement Plans
Components of Net Periodic Benefit Cost [Abstract]
Service cost	$ 1,813	$ 1,908	$ 5,439	$ 5,724
Interest cost	2,863	2,794	8,588	8,383
Expected return on plan assets	(4,907)	(5,229)	(14,723)	(15,687)
Amortization of net actuarial losses (gains)	1,266	1,403	3,798	4,208
Amortization of prior service cost (credit)	(57)	(60)	(163)	(179)
Settlements and curtailments	5,671	4,732	5,671	4,732
Net periodic benefit cost (benefit)	6,649	5,548	8,610	7,181
Other Postretirement Benefit Plans
Components of Net Periodic Benefit Cost [Abstract]
Service cost	327	377	981	1,131
Interest cost	173	163	521	487
Expected return on plan assets	(2,625)	(2,216)	(7,876)	(6,647)
Amortization of net actuarial losses (gains)	(776)	(425)	(2,328)	(1,273)
Amortization of prior service cost (credit)	123	53	367	159
Settlements and curtailments	0	0	0	0
Net periodic benefit cost (benefit)	$ (2,778)	$ (2,048)	(8,335)	$ (6,143)
Pension Plan
Components of Net Periodic Benefit Cost [Abstract]
Company contribution to qualified pension plan			$ 6,300