Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		1 Months Ended	3 Months Ended		6 Months Ended			1 Months Ended		1 Months Ended		3 Months Ended	1 Months Ended	3 Months Ended		1 Months Ended		3 Months Ended		6 Months Ended		1 Months Ended	3 Months Ended	1 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended		1 Months Ended			6 Months Ended				1 Months Ended		1 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Jul. 28, 2012	Jul. 30, 2011	Jul. 28, 2012 Cost of goods sold	Jul. 30, 2011 Cost of goods sold	Jul. 28, 2012 Cost of goods sold	Jul. 30, 2011 Cost of goods sold	Jul. 28, 2012 Selling, General and Administrative Expense	Jul. 30, 2011 Selling, General and Administrative Expense	Jul. 28, 2012 Selling, General and Administrative Expense	Jul. 30, 2011 Selling, General and Administrative Expense	Jun. 30, 1996 ESPP	Jul. 28, 2012 ESPP	Jul. 30, 2011 ESPP	Jul. 28, 2012 ESPP	Jul. 30, 2011 ESPP	Jun. 14, 2006 1996 Equity Incentive Plan	Jun. 14, 2006 1996 Equity Incentive Plan Maximum	Jun. 05, 2012 2006 Equity Incentive Plan	Mar. 31, 2012 2006 Equity Incentive Plan Chief Executive Officer	Mar. 31, 2011 2006 Equity Incentive Plan Chief Executive Officer	Jul. 28, 2012 2006 Equity Incentive Plan Chief Executive Officer	Jun. 05, 2012 2006 Equity Incentive Plan Maximum	Jul. 28, 2012 2006 Equity Incentive Plan Restricted Stock	Jul. 30, 2011 2006 Equity Incentive Plan Restricted Stock	Mar. 31, 2012 2006 Equity Incentive Plan Restricted Stock Director	Jun. 30, 2011 2006 Equity Incentive Plan Restricted Stock Director	Jul. 28, 2012 2006 Equity Incentive Plan Restricted Stock Director	Jul. 30, 2011 2006 Equity Incentive Plan Restricted Stock Director	Jul. 28, 2012 2006 Equity Incentive Plan Restricted Stock Director	Jul. 30, 2011 2006 Equity Incentive Plan Restricted Stock Director	Feb. 28, 2011 2006 Equity Incentive Plan Restricted Stock Chief Executive Officer	Apr. 30, 2011 2006 Equity Incentive Plan Restricted Stock Chief Executive Officer	Apr. 30, 2012 2006 Equity Incentive Plan Restricted Stock Independent consultant	Jul. 28, 2012 2006 Equity Incentive Plan Restricted Stock Independent consultant	Jul. 28, 2012 2006 Equity Incentive Plan Restricted Stock Independent consultant	Jul. 28, 2012 2006 Equity Incentive Plan Employee Stock Option	Jul. 30, 2011 2006 Equity Incentive Plan Employee Stock Option	Mar. 31, 2011 2006 Equity Incentive Plan Employee Stock Option Employees	Mar. 31, 2009 2006 Equity Incentive Plan Performance Awards	Mar. 31, 2009 2006 Equity Incentive Plan Performance Awards Maximum	Jul. 28, 2012 2012 Equity Incentive Plan	Jul. 28, 2012 2012 Equity Incentive Plan Maximum	Jul. 28, 2012 2012 Equity Incentive Plan Minimum	Jul. 28, 2012 2012 Equity Incentive Plan Minimum Persons possessing 10% or more of voting power	Jun. 30, 2012 2012 Equity Incentive Plan Restricted Stock Director	Jun. 05, 2012 1996 NEDSOP	Jun. 05, 2012 1996 NEDSOP Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future grant														692,372		692,372		732,456		942,602																							3,856,736					34,976
Aggregate number of shares authorized for grant													1,350,000					18,300,000		3,082,456																												720,000
Options, expiration period																			10 years					10 years																				8 years					10 years
Exercise price percentage on fair market value of common stock on date of grant																																													100.00%	110.00%
Number of additional shares authorized for grant																																											3,100,000
Stock Purchase Plan discount													15.00%
Share based compensation expense	$ 1,067,000	$ 1,863,000	$ 2,068,000	$ 2,724,000	$ 172,000	$ 105,000	$ 333,000	$ 218,000	$ 900,000	$ 1,800,000	$ 1,700,000	$ 2,500,000		$ 42,000	$ 39,000	$ 84,000	$ 78,000												$ 50,000	$ 47,000	$ 99,000	$ 99,000		$ 98,000		$ 13,000	$ 17,000
Award grants in period																											515	25,387					17,568		2,525							100,000					21,008
Vesting period																															1 year									4 years
Number of options granted			1,683,354																		100,000	500,000																		440,000
Market value common stock as of grant date																																									$ 9.56
Unrecognized expense, weighted average recognition period	2 years 318 days	2 years 281 days																					3 years 245 days		285 days	263 days												2 years 245 days	3 years 245 days		3 years
Total fair value of shares vested	600,000	1,000,000	1,500,000	2,300,000
Unrecognized expense	$ 8,000,000	$ 5,100,000	$ 8,000,000	$ 5,100,000																			$ 300,000		$ 175,000	$ 150,000												$ 300,000	$ 1,000,000
Weighted average fair value, grant date																							$ 3.44