Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 11,603	$ 16,168
Foreign currency translation adjustments	6,065	13,419
Net change in:
Deferred (gains) losses on cash flow hedges, net of taxes of $288 and $57, respectively	(946)	66
Unrecognized retirement obligations, net of taxes of $(1,248) and $(1,367), respectively	2,074	2,257
Other comprehensive income	7,193	15,742
Comprehensive income	$ 18,796	$ 31,910

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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