Note 4 - Diluted Net Income Per Share - Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Feb. 26, 2017	Feb. 28, 2016	Feb. 26, 2017	Feb. 28, 2016
Numerator:
Net income (loss) applicable to Common Stockholders	$ 3,500	$ (21,190)	$ 8,138	$ (16,370)
Denominator:
Weighted average shares for basic net income per share (in shares)	27,286	27,054	27,252	27,026
Effect of dilutive securities:
Stock options and restricted stock units (in shares)	396		356
Weighted average shares for diluted net income per share (in shares)	27,682	27,054	27,608	27,026
Diluted net income (loss) per share (in dollars per share)	$ 0.13	$ (0.78)	$ 0.29	$ (0.61)

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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