Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at Dec. 29, 2017	$ 107,275	$ 56	$ 288,297	$ (134,054)	$ (38,515)	$ (8,509)
Balance, Shares at Dec. 29, 2017		55,745		(26,945)
Issuance of common stock	(3,003)	$ 1	(3,004)
Issuance of common stock, Shares		721
Treasury stock purchased	(964)		1,346	$ (2,310)
Treasury stock purchased, Shares				(126)
Amortization of restricted stock units and common stock subject to vesting requirements	3,557		3,557
Net income	7,367				7,367
Foreign currency translation	1,152					1,152
Balance at Mar. 30, 2018	115,384	$ 57	290,196	$ (136,364)	(31,148)	(7,357)
Ending Balance, Shares at Mar. 30, 2018		56,466		(27,071)
Balance at Dec. 29, 2017	107,275	$ 56	288,297	$ (134,054)	(38,515)	(8,509)
Balance, Shares at Dec. 29, 2017		55,745		(26,945)
Net income	18,888
Foreign currency translation	(1,194)
Balance at Jun. 29, 2018	121,632	$ 57	292,665	$ (136,364)	(25,023)	(9,703)
Ending Balance, Shares at Jun. 29, 2018		56,522		(27,071)
Balance at Mar. 30, 2018	115,384	$ 57	290,196	$ (136,364)	(31,148)	(7,357)
Balance, Shares at Mar. 30, 2018		56,466		(27,071)
Issuance of common stock	205		205
Issuance of common stock, Shares		56
Amortization of restricted stock units and common stock subject to vesting requirements	2,264		2,264
Dividends declared	(5,396)				(5,396)
Net income	11,521				11,521
Foreign currency translation	(2,346)					(2,346)
Balance at Jun. 29, 2018	121,632	$ 57	292,665	$ (136,364)	(25,023)	(9,703)
Ending Balance, Shares at Jun. 29, 2018		56,522		(27,071)
Balance at Dec. 28, 2018	123,590	$ 57	296,955	$ (136,604)	(25,424)	(11,394)
Balance, Shares at Dec. 28, 2018		56,615		(27,086)
Issuance of common stock	(2,372)	$ 1	(2,373)
Issuance of common stock, Shares		394
Treasury stock purchased	(1,616)			$ (1,616)
Treasury stock purchased, Shares				(102)
Amortization of restricted stock units and common stock subject to vesting requirements	2,394		2,394
Net income	7,094				7,094
Foreign currency translation	657					657
Balance at Mar. 29, 2019	129,747	$ 58	296,976	$ (138,220)	(18,330)	(10,737)
Ending Balance, Shares at Mar. 29, 2019		57,009		(27,188)
Balance at Dec. 28, 2018	123,590	$ 57	296,955	$ (136,604)	(25,424)	(11,394)
Balance, Shares at Dec. 28, 2018		56,615		(27,086)
Net income	14,083
Foreign currency translation	(15)
Balance at Jun. 28, 2019	131,201	$ 58	299,342	$ (139,660)	(17,130)	(11,409)
Ending Balance, Shares at Jun. 28, 2019		57,130		(27,280)
Balance at Mar. 29, 2019	129,747	$ 58	296,976	$ (138,220)	(18,330)	(10,737)
Balance, Shares at Mar. 29, 2019		57,009		(27,188)
Issuance of common stock	405		405
Issuance of common stock, Shares		121
Treasury stock purchased	(1,440)			$ (1,440)
Treasury stock purchased, Shares				(92)
Amortization of restricted stock units and common stock subject to vesting requirements	1,961		1,961
Dividends declared	(5,789)				(5,789)
Net income	6,989				6,989
Foreign currency translation	(672)					(672)
Balance at Jun. 28, 2019	$ 131,201	$ 58	$ 299,342	$ (139,660)	$ (17,130)	$ (11,409)
Ending Balance, Shares at Jun. 28, 2019		57,130		(27,280)