Stock Option and Stock Award Plans (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 02, 2013	Mar. 03, 2012	Feb. 26, 2011
Stock options and stock award Plans
Stock-based compensation costs	$ 17,717,000	$ 15,861,000	$ 17,336,000
Shares of common stock authorized under stock-based compensation plans	109,764
Fair value assumptions
Dividend rate (as a percent)	0.00%	0.00%	0.00%
Maximum
Stock options and stock award Plans
Term of options	10 years
Stock options
Fair value assumptions
Expected stock price volatility (as a percent)	85.00%	79.00%	79.00%
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%
Risk-free interest rate (as a percent)	0.71%	1.45%	1.92%
Expected option life	5 years 6 months	5 years 6 months	5 years 6 months
Plan Awards, Additional Disclosures
Weighted average fair value of options granted (in dollars per share)	$ 0.91	$ 0.82	$ 0.71
Shares
Outstanding at the beginning of the period (in shares)	73,798	74,298	76,114
Granted (in shares)	12,020	23,200	17,443
Exercised (in shares)	(1,535)	(896)	(244)
Cancelled (in shares)	(3,283)	(22,804)	(19,015)
Outstanding at the end of the period (in shares)	81,000	73,798	74,298
Vested or expected to vest at the end of the period (in shares)	72,742
Exercisable at the end of the period (in shares)	42,893
Weighted Average Exercise Price Per Share
Outstanding at the beginning of the period (in dollars per share)	$ 1.52	$ 2.47	$ 3.08
Granted (in dollars per share)	$ 1.32	$ 1.19	$ 1.07
Exercised (in dollars per share)	$ 1.06	$ 1.02	$ 0.92
Cancelled (in dollars per share)	$ 2.08	$ 4.31	$ 3.66
Outstanding at the end of the period (in dollars per share)	$ 1.48	$ 1.52	$ 2.47
Vested or expected to vest at the end of the period (in dollars per share)	$ 1.51
Exercisable at the end of the period (in dollars per share)	$ 1.71
Weighted Average Remaining Contractual Term
Outstanding at the end of the period	6 years 9 months 14 days
Vested or expected to vest at the end of the period	6 years 7 months 28 days
Exercisable at the end of the period	5 years 9 months
Aggregate Intrinsic Value
Outstanding at the end of the period	38,963,000
Vested or expected to vest at the end of the period	35,262,000
Exercisable at the end of the period	21,534,000
Additional General Disclosures
Total unrecognized pre-tax compensation costs, net of forfeitures	18,202,000
Weighted-average period over which remaining share-based cost is expected to be recognized	2 years 4 months 6 days
Cash received from stock option exercises	1,646,000	914,000	226,000
Income tax benefit from stock options	0	0	0
Total intrinsic value of options exercised	714,000	255,000	81,000
Stock options | Non-employee director
Additional General Disclosures
Vesting period	3 years
Stock options | Employee
Additional General Disclosures
Vesting period	4 years
Restricted stock
Additional General Disclosures
Total unrecognized pre-tax compensation costs, net of forfeitures	9,465,000
Weighted-average period over which remaining share-based cost is expected to be recognized	2 years 22 days
Shares
Outstanding at the beginning of the period (in shares)	11,506	7,078	5,944
Granted (in shares)	5,450	8,525	4,574
Vested (in shares)	(3,917)	(3,366)	(3,055)
Cancelled (in shares)	(362)	(731)	(385)
Outstanding at the end of the period (in shares)	12,677	11,506	7,078
Weighted Average Grant Date Fair Value
Outstanding at the beginning of the period (in dollars per share)	$ 1.20	$ 1.12	$ 2.26
Granted (in dollars per share)	$ 1.31	$ 1.23	$ 1.07
Vested (in dollars per share)	$ 1.18	$ 1.11	$ 3.21
Cancelled (in dollars per share)	$ 1.26	$ 1.16	$ 1.65
Outstanding at the end of the period (in dollars per share)	$ 1.25	$ 1.20	$ 1.12
Additional Disclosures
Total fair value of awards vested during the period	$ 4,623,000	$ 3,724,000	$ 9,819,000
Restricted stock | Maximum
Additional General Disclosures
Vesting period	3 years
Restricted stock | Non-employee director
Additional Disclosures
Portion of non-employee director award vesting in year one (as a percent)			80.00%
Portion of non-employee director award vesting in year two (as a percent)			10.00%
Portion of non-employee director award vesting in year three (as a percent)			10.00%
Stock options and restricted stock
Additional Disclosures
Portion of employee stock options and awards vesting in year three (as a percent)		50.00%
Portion of employee stock options and awards vesting in year four (as a percent)		50.00%
1999 Plan
Stock options and stock award Plans
Shares of common stock authorized under stock-based compensation plans	10,000
2000 Plan
Stock options and stock award Plans
Shares of common stock reserved for the granting of stock options and other incentive awards	22,000
2001 Plan
Stock options and stock award Plans
Shares of common stock authorized under stock-based compensation plans	20,000
2004 Omnibus Equity Plan
Stock options and stock award Plans
Shares of common stock authorized under stock-based compensation plans	20,000
2006 Omnibus Equity Plan
Stock options and stock award Plans
Shares of common stock available for grant	50,000
2010 Omnibus Equity Plan
Stock options and stock award Plans
Shares of common stock available for grant	35,000
2012 Omnibus Equity Plan
Stock options and stock award Plans
Shares of common stock available for grant	28,500