Shareholders' Equity - Summary of Combined Stock Option Activity and Related Information for Stock Options Granted (Details) - Stock Options - 2010 Plan and 2007 Plan	3 Months Ended
Aug. 01, 2020 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding [Roll Forward]
Outstanding - beginning balance (in shares) \| shares	106,668
Exercised (in shares) \| shares	(5,000)
Outstanding - ending balance (in shares) \| shares	101,668
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Wtd. Avg. Exercise Price, Outstanding - beginning balance (in dollars per share) \| $ / shares	$ 35.76
Wtd. Avg. Exercise Price, Exercised (in dollars per share) \| $ / shares	10.55
Wtd. Avg. Exercise Price, Outstanding - ending balance (in dollars per share) \| $ / shares	$ 37.01

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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

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