Note 2 - Loss Per Share - Weighted-average Common and Dilutive Potential Common Shares Outstanding (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 28, 2017	Mar. 01, 2016	Feb. 28, 2017	Mar. 01, 2016
Net loss	$ (19,805)	$ (3,086)	$ (97,453)	$ (23,079)
Weighted-average common shares outstanding (in shares)	60,262	60,918	60,074	61,239
Dilutive effect of stock options and restricted stock (in shares)
Weighted average common and dilutive potential common shares outstanding (in shares)	60,262	60,918	60,074	61,239
Basic loss per share (in dollars per share)	$ (0.33)	$ (0.05)	$ (1.62)	$ (0.38)
Diluted loss per share (in dollars per share)	$ (0.33)	$ (0.05)	$ (1.62)	$ (0.38)