Effect of Recording Equity-Based Compensation (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Equity Based Compensation Related to Employee Stock Purchase Programs [Line Items]
Total equity-based compensation	$ 754,000	$ 943,000	$ 1,836,000	$ 2,941,000
Tax effect on equity-based compensation	(8,000)	(205,000)	(18,000)	(706,000)
Net effect on net loss	746,000	738,000	1,818,000	2,235,000
Stock Options
Equity Based Compensation Related to Employee Stock Purchase Programs [Line Items]
Total equity-based compensation	375,000	523,000	651,000	1,843,000
RSUs
Equity Based Compensation Related to Employee Stock Purchase Programs [Line Items]
Total equity-based compensation	130,000	88,000	314,000	111,000
Employee Stock Purchase Plan
Equity Based Compensation Related to Employee Stock Purchase Programs [Line Items]
Total equity-based compensation	$ 249,000	$ 332,000	$ 871,000	$ 987,000