CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standard	$ 28,971	$ 500	$ 842	$ 268,327	$ (240,104)	$ 500	$ (94)
Balance at beginning of the period at Dec. 29, 2018	28,971	500	$ 842	268,327	(240,104)	500	(94)
Balance at beginning of the period (shares) at Dec. 29, 2018			84,196
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	10,399			10,399
Common stock issued under employee benefit plans	2,708		$ 16	2,692
Common stock issued under employee benefit plans (in shares)			1,579
Common stock withheld related to net share settlement of stock-based compensation (in shares)			(7)
Adoption of new accounting standard	28,971	500	$ 842	281,418	(194,287)	500	(129)
Dividends	(375)				(375)
Other comprehensive loss	(35)						(35)
Net income	45,692				45,692
Balance at end of the period at Sep. 28, 2019	87,860		$ 858	281,418	(194,287)		(129)
Balance at end of the period (shares) at Sep. 28, 2019			85,775
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standard	63,952	(56)	$ 848	278,671	(215,533)	(56)	(34)
Balance at beginning of the period at Jun. 29, 2019	63,952	(56)	$ 848	278,671	(215,533)	(56)	(34)
Balance at beginning of the period (shares) at Jun. 29, 2019			84,820
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	2,113			2,113
Common stock issued under employee benefit plans	644		$ 10	634
Common stock issued under employee benefit plans (in shares)			955
Adoption of new accounting standard	87,860	$ (56)	$ 858	281,418	(194,287)	$ (56)	(129)
Other comprehensive loss	(95)						(95)
Net income	21,302				21,302
Balance at end of the period at Sep. 28, 2019	87,860		$ 858	281,418	(194,287)		(129)
Balance at end of the period (shares) at Sep. 28, 2019			85,775
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standard	87,860		$ 858	281,418	(194,287)		(129)
Adoption of new accounting standard	122,005		868	310,678	(189,545)		4
Balance at beginning of the period at Dec. 28, 2019	122,005		$ 868	310,678	(189,545)		4
Balance at beginning of the period (shares) at Dec. 28, 2019			86,774
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	6,315			6,315
Common stock issued under employee benefit plans	2,033		$ 3	2,030
Common stock issued under employee benefit plans (in shares)			319
Common stock withheld related to net share settlement of stock-based compensation	(1,027)			(1,027)
Common stock withheld related to net share settlement of stock-based compensation (in shares)			(29)
Adoption of new accounting standard	122,005		$ 868	317,996	(189,545)		4
Other comprehensive loss	(100)						(100)
Net income	93,407				93,407
Balance at end of the period at Sep. 26, 2020	222,633		$ 871	317,996	(96,138)		(96)
Balance at end of the period (shares) at Sep. 26, 2020			87,064
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standard	169,029		$ 870	315,405	(147,583)		337
Balance at beginning of the period at Jun. 27, 2020	169,029		$ 870	315,405	(147,583)		337
Balance at beginning of the period (shares) at Jun. 27, 2020			87,004
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	2,279			2,279
Common stock issued under employee benefit plans	636		$ 1	635
Common stock issued under employee benefit plans (in shares)			67
Common stock withheld related to net share settlement of stock-based compensation	(323)			(323)
Adoption of new accounting standard	169,029		$ 871	317,996	(96,138)		(96)
Other comprehensive loss	(433)						(433)
Net income	51,445				51,445
Balance at end of the period at Sep. 26, 2020	222,633		$ 871	317,996	(96,138)		(96)
Balance at end of the period (shares) at Sep. 26, 2020			87,064
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standard	$ 222,633		$ 871	$ 317,996	$ (96,138)		$ (96)