Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 1,950	$ 10,317
Other comprehensive (loss) income, net of tax:
Foreign currency translation (loss) gain, net of tax	(7,349)	20,904
Change in unrecognized gains (losses) on derivative instruments:
Change in fair value of derivatives	6,414	17,672
Tax provision	(1,488)	(3,762)
Change in unrecognized gains (losses) on derivative instruments, net of tax	4,926	13,910
Defined benefit pension plan:
Amortization of actuarial loss	52	109
Tax provision	(11)	(22)
Pension changes, net of tax	41	87
Other comprehensive (loss) income, net of tax	(2,382)	34,901
Comprehensive (loss) income	$ (432)	$ 45,218