Accumulated Other Comprehensive Income (AOCI) (Schedule of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 698,683
Ending balance	666,961
Translation adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(122,852)	$ (115,976)
Other comprehensive income/(loss) before reclassifications	(25,747)	(654)
Interest expense related to swaps reclassified to the Consolidated Statements of Income, net of tax
Pension and postretirement liability adjustments reclassified to Consolidated Statements of Income, net of tax
Adjustment related to prior period change in opening valuation allowance
Net current period other comprehensive income	(25,747)	(654)
Ending balance	(148,599)	(116,630)
Pension and postretirement liability adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(49,994)	(47,109)
Other comprehensive income/(loss) before reclassifications	792	(152)
Interest expense related to swaps reclassified to the Consolidated Statements of Income, net of tax
Pension and postretirement liability adjustments reclassified to Consolidated Statements of Income, net of tax	98	11
Adjustment related to prior period change in opening valuation allowance		(1,346)
Net current period other comprehensive income	890	(1,487)
Ending balance	(49,104)	(48,596)
Derivative valuation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(3,135)	4,697
Other comprehensive income/(loss) before reclassifications	(8,011)	(2,514)
Interest expense related to swaps reclassified to the Consolidated Statements of Income, net of tax	303	(337)
Pension and postretirement liability adjustments reclassified to Consolidated Statements of Income, net of tax
Adjustment related to prior period change in opening valuation allowance
Net current period other comprehensive income	(7,708)	(2,851)
Ending balance	(10,843)	1,846
Total Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(175,981)	(158,388)
Other comprehensive income/(loss) before reclassifications	(32,966)	(3,320)
Interest expense related to swaps reclassified to the Consolidated Statements of Income, net of tax	303	(337)
Pension and postretirement liability adjustments reclassified to Consolidated Statements of Income, net of tax	98	11
Adjustment related to prior period change in opening valuation allowance		(1,346)
Net current period other comprehensive income	(32,565)	(4,992)
Ending balance	$ (208,546)	$ (163,380)