Condensed Consolidated Statement Of Comprehensive Income - 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	$ 13,186	$ 47,527	$ 41,400	$ 81,893
Other comprehensive (loss) income:
Net foreign currency translation adjustment	1,239	(1,495)	(3,501)	(2,669)
Actuarial gain on Dutch pension plans	6,299	0	6,299	0
Unrealized gain (loss) on fair value of derivative instruments	442	(1,888)	1,642	(2,042)
Total comprehensive income	$ 21,166	$ 44,144	$ 45,840	$ 77,182