Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 7,270	$ 8,135	$ 9,220	$ 18,452
Other comprehensive income (loss), net of tax:
Foreign currency translation gain (loss), net of tax	8,033	(35,233)	684	(14,329)
Change in unrecognized gains (losses) on derivative instruments:
Change in fair value of derivatives	2,130	(22,566)	8,544	(4,894)
Tax (provision) benefit	(274)	4,577	(1,762)	815
Change in unrecognized gains (losses) on derivative instruments, net of tax	1,856	(17,989)	6,782	(4,079)
Defined benefit pension plan:
Amortization of actuarial loss	53	68	105	177
Tax provision	(11)	(24)	(22)	(46)
Pension changes, net of tax	42	44	83	131
Other comprehensive income (loss), net of tax	9,931	(53,178)	7,549	(18,277)
Comprehensive income (loss)	$ 17,201	$ (45,043)	$ 16,769	$ 175

Other comprehensive income foreign currency translation gain loss arising during period net of taxes.

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