Retirement Plans, Components of Net Periodic Benefit Cost, Pension Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net periodic benefit cost [Abstract]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Recognition of actuarial loss	$ (22,438)	$ (58,147)	$ (44,491)
Pension Plan [Member]
Components of net periodic benefit cost [Abstract]
Service cost	3,695	6,538	7,961
Interest cost	18,356	14,779	14,239
Expected return on plan assets	(22,910)	(28,399)	(26,244)
Amortization of actuarial loss	0	34	4,193
Net periodic benefit cost	(859)	(7,048)	(149)
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial (gain) loss	(22,583)	(58,015)	(44,583)
Recognition of actuarial loss	0	(34)	(4,193)
Total recognized in other comprehensive income	(22,583)	(58,049)	(48,776)
Total recognized in net periodic benefit cost and other comprehensive income	(23,442)	(65,097)	(48,627)
SERP [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	0	0
Interest cost	43	29	31
Expected return on plan assets	0	0	0
Amortization of actuarial loss	23	30	40
Net periodic benefit cost	66	59	71
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial (gain) loss	91	(74)	(12)
Recognition of actuarial loss	(23)	(30)	(40)
Total recognized in other comprehensive income	68	(104)	(52)
Total recognized in net periodic benefit cost and other comprehensive income	$ 134	$ (45)	$ 19