Income Taxes - Operating Losses and Tax Credits (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Apr. 02, 2016
Income Tax Disclosure [Abstract]
Federal net operating losses	$ 35,566	$ 27,430
Federal net operating losses	3,679	3,467
Foreign operating losses and tax credits	12,504	12,173
Federal research credits	22,590	21,336
State research credits	4,409	4,480
Federal minimum tax credit	935	990
Federal capital losses	5,015	8,022
Net operating loss carryforward, net of tax and tax credits	$ 84,698	$ 77,898

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

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