Note 6 - Stock-based Compensation - Option Activity (Details) - $ / shares	3 Months Ended	6 Months Ended
May 27, 2018	Aug. 26, 2018
Outstanding options (in shares)	885,554	885,554
Balance, weighted average exercise price (in dollars per share)	$ 17.55	$ 17.55
Outstanding options, granted (in shares)	2,650	2,650
Granted, weighted average exercise price (in dollars per share)	$ 17.75
Outstanding options, exercised (in shares)	(35,537)	(35,537)
Exercised, weighted average exercise price (in dollars per share)	$ 17.55
Outstanding options, terminated or expired (in shares)	(99,413)
Terminated or expired, weighted average exercise price (in dollars per share)	$ 19.63
Outstanding options (in shares)	753,254
Balance, weighted average exercise price (in dollars per share)	$ 17.28
Balance, weighted average remaining contractual term (Year)	5 years 10 days
Vested and exercisable (in shares)	628,548
Vested and exercisable, weighted average exercise price (in dollars per share)	$ 18.01
Vested and exercisable, weighted average remaining contractual term (Year)	4 years 240 days

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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