Interim Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 20,033	$ 17,418	$ 48,550	$ 53,338
Other comprehensive income (loss):
Foreign currency translation adjustment	8,606	(9,791)	(6,244)	(7,877)
Net gain on pension and other post-retirement benefits	245	215	737	645
Unrealized (loss) gain on derivative instruments	(1,247)	1,864	(8,106)	1,852
Other comprehensive income (loss) before income tax expense	7,604	(7,712)	(13,613)	(5,380)
Income tax benefit (expense) related to items of other comprehensive income (loss)	210	(46)	1,431	(136)
Other comprehensive income (loss)	7,814	(7,758)	(12,182)	(5,516)
Comprehensive income	$ 27,847	$ 9,660	$ 36,368	$ 47,822