Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 28, 2012	Oct. 23, 2011	Oct. 28, 2012	Oct. 23, 2011
Income (loss) applicable to common shares:
Income (loss) from continuing operations	$ (4,341)	$ (1,030)	$ 403	$ (3,589)
Loss from discontinued operations	(2,312)	(427)	(395)	(191)
Net income (loss)	$ (6,653)	$ (1,457)	$ 8	$ (3,780)
Denominator:
Denominator for basic earnings (loss) per share - weighted average shares	39,336,134	38,753,049	39,177,208	38,515,099
Effect of dilutive securities Employee stock options (in shares)			14,867
Denominator for diluted earnings (loss) per share - adjusted weighted average shares and assumed conversions	39,336,134	38,753,049	39,192,075	38,515,099
Basic earnings (loss) per share:
Income (loss) from continuing operations (in dollars per share)	$ (0.11)	$ (0.03)	$ 0.01	$ (0.09)
Loss from discontinued operations (in dollars per share)	$ (0.06)	$ (0.01)	$ (0.01)	$ (0.01)
Net income (loss) (in dollars per share)	$ (0.17)	$ (0.04)	$ 0.00	$ (0.10)
Diluted earnings (loss) per share:
Income (loss) from continuing operations (in dollars per share)	$ (0.11)	$ (0.03)	$ 0.01	$ (0.09)
Loss from discontinued operations (in dollars per share)	$ (0.06)	$ (0.01)	$ (0.01)	$ (0.01)
Net income (loss) (in dollars per share)	$ (0.17)	$ (0.04)	$ 0.00	$ (0.10)
Anti-dilutive shares excluded from calculation of EPS	1,009,160	1,169,710	1,009,160	1,069,710
Potentially dilutive shares excluded from calculation of EPS	30,236	22,045		38,074