Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 18,960	$ 20,179	$ 43,701	$ 34,520
Other comprehensive income:
Change in cumulative translation adjustment	(799)	591	(463)	689
Cash flow hedges:
Change in fair value of derivatives	(71)	679	(62)	692
Adjustment for net gain (loss) realized and included in net income	(24)		(910)	7
Total change in unrealized gain (loss) on derivative instruments	(95)	679	(972)	699
Other comprehensive income (loss), net of tax	(894)	1,270	(1,435)	1,388
Comprehensive income	$ 18,066	$ 21,449	$ 42,266	$ 35,908

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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