Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (5,230)	$ 14,582	$ 360	$ 30,576
Other comprehensive income (loss), before tax:
Unrealized gains (losses) on derivative instruments	124	(6,003)	816	(7,700)
Unrealized gains (losses) on available-for-sale securities	69	(27)	31	(82)
Other comprehensive income (loss), before tax	193	(6,030)	847	(7,782)
Tax benefit (provision) related to derivative instruments	(15)	809	(76)	1,005
Tax benefit (provision) related to available-for-sale securities	(16)	9	(27)	29
Other comprehensive income (loss), net of tax	162	(5,212)	744	(6,748)
Comprehensive income (loss)	$ (5,068)	$ 9,370	$ 1,104	$ 23,828