CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 32,449	$ 34,259	$ 40,043	$ 63,667
Other Comprehensive Income (Loss), before Tax [Abstract]
Foreign currency translation and other adjustments	8,753	(50)	(16,202)	(2,202)
Pension/postretirement settlements and curtailments	378	0	378	0
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent [Abstract]
Prior service credit	(1,114)	(1,105)	(2,228)	(2,210)
Net actuarial loss	1,232	1,118	2,476	2,239
Payments and amortization related to interest rate swaps included in earnings	1,116	(420)	1,523	(872)
Derivative valuation adjustment	(1,366)	(5,887)	(12,130)	(9,264)
Income taxes related to items of other comprehensive income/(loss):
Pension/postretirement settlements and curtailments	(113)	0	(113)	0
Amortization of pension liability adjustment	(30)	(4)	(62)	(9)
Payments and amortization related to interest rate swaps included in earnings	(286)	108	(390)	223
Derivative valuation adjustment	349	1,504	3,102	2,367
Comprehensive income	41,368	29,523	16,397	53,939
Comprehensive income/(loss) attributable to the noncontrolling interest	247	207	(1,159)	417
Comprehensive income/(loss) attributable to the Company	$ 41,121	$ 29,316	$ 17,556	$ 53,522