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Employee 401(k) Savings Plan - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Apr. 28, 2018 | Apr. 29, 2017 | Apr. 30, 2016
Retirement Benefits [Abstract] |  |  |
Employer matching contribution, percent | 3.00% |  |
Employer 401(k) contribution | $ 1.4 | $ 1.3 | $ 1.3

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- References No definition available. + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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