Retirement Plans (Components of Net Periodic Benefits Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,927	$ 1,979	$ 3,906	$ 3,959
Interest cost	6,010	5,963	11,930	11,751
Expected return on plan assets	(11,906)	(11,178)	(23,823)	(22,356)
Amortization of net (gain) or loss and prior service costs	1,420	1,911	2,624	3,681
Net periodic benefit cost	$ (2,549)	$ (1,325)	$ (5,363)	$ (2,965)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense
Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	$ 10	$ 18	$ (21)
Interest cost	154	149	308	365
Amortization of net (gain) or loss and prior service costs	(185)	(158)	(370)	(409)
Net periodic benefit cost	$ (22)	$ 1	$ (44)	$ (65)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense	Payroll Taxes Healthcare Costs Pension And Other Postretirement Benefit Expense