Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 5,983	$ 839	$ 1,810	$ 13,682
Other comprehensive income (loss), before tax:
Change in unrealized gains and losses on derivatives	(418)	(2)	(15)	21
Change in unrealized gains and losses on available-for-sale investments	0	1	0	16
Other comprehensive income (loss), before tax	(418)	(1)	(15)	37
Tax benefit (provision) related to derivatives	54	0	1	(6)
Tax provision related to available-for-sale investments	0	(1)	0	(4)
Other comprehensive income (loss), net of tax	(364)	(2)	(14)	27
Comprehensive income	$ 5,619	$ 837	$ 1,796	$ 13,709