CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract]
Net income	$ 70,800	$ 27,386	$ 169,979	$ 69,174
Unrealized gain (loss) on defined benefit plan, net of tax	851	288	7,706	6,563
Unrealized gain (loss) on swaps and collars, net of tax	1,052	212	2,851	(409)
Unrealized foreign currency (loss) gain, net of tax	(4,343)	20,887	4,768	18,006
Comprehensive income	68,360	48,773	185,304	80,208
Less: Comprehensive income attributable to noncontrolling interest	(2,376)	(234)	(6,729)	(821)
Total comprehensive income attributable to common stockholders	$ 65,984	$ 48,539	$ 178,575	$ 79,387