Sale of Non-Digital Division Assets (Details) - Non-Digital Division [Member] $ in Thousands	12 Months Ended
Apr. 28, 2018 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets sold	$ 517
Gain from sale of non-digital division	$ 1,267

Amount classified as assets attributable to disposal group held for sale or disposed of.

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