Summary of Significant Accounting Policies (Schedule of Accumulated Other Comprehensive Income (loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	$ 13,372	$ (6,981)	$ 20,035
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(52,526)	(8,890)	(8,865)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	3,042	(287)	(1,643)
Other comprehensive income (loss)	65,898	1,909	28,900
Equity	155,653	201,762	184,722	$ 109,055
Other Comprehensive Income (Loss), before Reclassifications, before Tax	3,511	3	(2,008)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Before reclassification, beforeTax	11,794	(1,256)	3,800
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax	1,935	(6,464)	23,932
Other Comprehensive Income (Loss), before Reclassifications, before Tax	17,240	(7,717)	25,724
OCI, Foreign Currency Transaction and Translation Gain (Loss), Arising During Period, Tax	(469)	(290)	365
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Before reclassification, Tax	(2,977)	(374)	(842)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax	(422)	1,400	(5,212)
Other Comprehensive Income (Loss) before Reclassifications, Tax	(3,868)	736	(5,689)
Unrealized foreign currency translation adjustment (net of tax expense of $469 in 2023, net of tax expense of $290 in 2022 and net of tax benefit of $365 in 2021)	3,042	(287)	(1,643)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Before reclassification, afterTax	8,817	(1,630)	2,958
Net gains (losses) and prior service costs (net of tax expense of $422 in 2023, net of tax benefit of $1,400 in 2022 and net of tax expense of $5,212 in 2021)	1,513	(5,064)	18,720
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax	0	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(7,580)	(2,461)	(5,513)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	101,323	13,606	16,862
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	93,743	11,145	11,349
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI Including Earnings Of Actuarial Loss For Pension Settlement, Tax	(43,261)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Income Tax (Expense) Benefit, Tax	2,044
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Tax	0	0	0
Reclassification from AOCI, Current Period, Tax		710	1,192
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax	(1,968)	(2,965)	(3,676)
Other Comprehensive Income (Loss) Reclassifications, Tax	(41,217)	(2,255)	(2,484)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Including Earnings Of Actuarial Loss For Pension Settlement, after Tax	58,062
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	0	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(5,536)	(1,751)	(4,321)
Amortization of prior service costs and net gains or losses (net of tax expense of $1,968 in 2023, net of tax expense of $2,965 in 2022 and net of tax expense of $3,676 in 2021)	7,065	10,641	13,186
Other Comprehensive Income (Loss), Derivatives, Net of Tax	3,281
Derivative financial instruments adjustment (net of tax expense of $933 in 2023, net of tax benefit of $336 in 2022 and net of tax benefit of $351 in 2021)		(3,381)	(1,363)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	59,575	5,577	31,906
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Equity	(83,037)	(86,079)	(85,792)	(84,149)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Equity	801	(2,480)	901	2,264
Pension And Other Postretirement Benefit Adjust
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Equity	539	(59,036)	(64,613)	(96,519)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(147,595)	(149,504)	(178,404)
Equity	(81,697)	(147,595)	(149,504)	$ (178,404)
Net gains (losses) and prior service costs (net of tax expense of $422 in 2023, net of tax benefit of $1,400 in 2022 and net of tax expense of $5,212 in 2021)		(5,064)	18,720
Amortization of prior service costs and net gains or losses (net of tax expense of $1,968 in 2023, net of tax expense of $2,965 in 2022 and net of tax expense of $3,676 in 2021)	7,065	10,641	13,186
Ending balance	$ (81,697)	$ (147,595)	$ (149,504)