Income (Loss) Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Aug. 31, 2013	Sep. 01, 2012	Aug. 31, 2013	Sep. 01, 2012
Numerator for income (loss) per share:
Net income (loss)	$ 32,827	$ (38,765)	$ 122,489	$ (66,853)
Accretion of redeemable preferred stock	(26)	(26)	(51)	(51)
Cumulative preferred stock dividends	(2,772)	(2,612)	(5,504)	(5,186)
Income (loss) attributable to common stockholders-basic	30,029	(41,403)	116,934	(72,090)
Add back-Interest on convertible notes			2,728
Income (loss) attributable to common stockholders-diluted	$ 30,029	$ (41,403)	$ 119,662	$ (72,090)
Denominator:
Basic weighted average shares	901,992	889,645	897,993	888,573
Outstanding options and restricted shares, net (in shares)	44,726		40,143
Convertible notes (in shares)			24,800
Diluted weighted average shares	946,718	889,645	962,936	888,573
Basic income (loss) per share (in dollars per share)	$ 0.03	$ (0.05)	$ 0.13	$ (0.08)
Diluted income (loss) per share (in dollars per share)	$ 0.03	$ (0.05)	$ 0.12	$ (0.08)
Antidilutive securities excluded from computation of earnings per share
Potential common shares excluded from the computation of diluted income (loss) per share	97,923	140,528	77,777	140,528
Stock options
Antidilutive securities excluded from computation of earnings per share
Potential common shares excluded from the computation of diluted income (loss) per share	39,014	83,591	43,668	83,591
Convertible notes
Antidilutive securities excluded from computation of earnings per share
Potential common shares excluded from the computation of diluted income (loss) per share	24,800	24,800		24,800
Convertible preferred stock
Antidilutive securities excluded from computation of earnings per share
Potential common shares excluded from the computation of diluted income (loss) per share	34,109	32,137	34,109	32,137
Restricted shares and restricted stock units
Antidilutive securities excluded from computation of earnings per share
Potential common shares excluded from the computation of diluted income (loss) per share			0	12,856