Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 24,253	$ 25,817	$ 67,955	$ 105,652
Other comprehensive loss, net of tax
Foreign currency translation adjustments	(5,097)	(1,222)	(8,478)	(14,624)
Unrealized net gains/(losses) on hedges of a net investment in a foreign operation	72		72
Unrealized net gains/(losses) on hedges of a net investment in a foreign operation		2		(6)
Unrealized net gains/(losses) on cash flow hedges	(396)		(6,996)
Unrealized net gains/(losses) on cash flow hedges		1,196		(361)
Gains/(losses) on defined benefit plans	121	(257)	138	493
Other comprehensive loss	(5,300)	(281)	(15,264)	(14,498)
Comprehensive income	$ 18,953	$ 25,536	$ 52,691	$ 91,154

Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss) Arising During Period, Net of Tax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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