Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 5,286	$ 5,716
Foreign currency translation adjustments	(5,163)	12,747
Net change in:
Deferred gains (losses) on cash flow hedges, net of taxes of $(834) and $583, respectively	2,222	(1,802)
Unrecognized retirement obligations, net of taxes of $(145) and $(977), respectively	846	3,075
Other comprehensive income (loss)	(2,095)	14,020
Comprehensive income	$ 3,191	$ 19,736

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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