Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Apr. 30, 2016	May 02, 2015	Apr. 26, 2014
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 9,067
Operating Loss Carryforwards [Line Items]
Deferred tax assets, gross	21,445	$ 18,315
Deferred tax asset valuation allowance	1,673	52	$ 2,297
Interest and penalties	232	14	$ 20
Accrued interest or penalties	94	$ 16
International
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	6,428
Deferred tax assets, gross	1,404
Canada
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	219
Ireland and Belgium [Domain]
Operating Loss Carryforwards [Line Items]
Deferred tax asset valuation allowance	$ 1,337