Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income
Beginning Balance Value at Dec. 29, 2012	$ 215,771	$ 23	$ 238,326	$ (23,850)	$ 1,272
Beginning Balance Shares at Dec. 29, 2012		23,250,429
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(14,146)			(14,146)
Employee benefit plan adjustment	151				151
Foreign currency translation adjustments	(818)				(818)
Unrealized gain (loss) on investments, net of tax	7				7
Issuance of common stock under stock-based compensation plans	3,734	$ 1	3,733
Issuance of common stock under stock-based compensation plans, Shares		619,617
Stock-based compensation expense	7,674		7,674
Repurchases and retirement of common stock	$ (5,000)		(5,000)
Repurchases and retirement of common stock, Shares	(332,771)	(332,771)
Ending Balance Value at Dec. 28, 2013	$ 207,373	$ 24	244,733	(37,996)	612
Ending Balance Shares at Dec. 28, 2013		23,537,275
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(31,118)			(31,118)
Employee benefit plan adjustment	(106)				(106)
Foreign currency translation adjustments	(3,239)				(3,239)
Unrealized gain (loss) on investments, net of tax	(36)				(36)
Issuance of common stock under stock-based compensation plans	5,255		5,255
Issuance of common stock under stock-based compensation plans, Shares		639,087
Stock-based compensation expense	6,752		6,752
Repurchases and retirement of common stock	$ (5,344)		(5,344)
Repurchases and retirement of common stock, Shares	(362,633)	(362,633)
Ending Balance Value at Dec. 27, 2014	$ 179,537	$ 24	251,396	(69,114)	(2,769)
Ending Balance Shares at Dec. 27, 2014	23,813,729	23,813,729
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,905			2,905
Employee benefit plan adjustment	(76)				(76)
Foreign currency translation adjustments	(2,344)				(2,344)
Unrealized gain (loss) on investments, net of tax	(13)				(13)
Issuance of common stock under stock-based compensation plans	2,792		2,792
Issuance of common stock under stock-based compensation plans, Shares		521,607
Stock-based compensation expense	6,248		6,248
Repurchases and retirement of common stock	$ (1,721)		(1,721)
Repurchases and retirement of common stock, Shares	(111,050)	(111,050)
Ending Balance Value at Dec. 26, 2015	$ 187,328	$ 24	$ 258,715	$ (66,209)	$ (5,202)
Ending Balance Shares at Dec. 26, 2015	24,224,286	24,224,286