Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
May 03, 2015	Apr. 27, 2014	Apr. 28, 2013
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Expected income tax provision (benefit) at U.S. federal statutory rate	35.00%	35.00%	35.00%
Foreign rate differential	(46.90%)	(18.30%)	38.30%
Share-based compensation expense	29.60%	2.50%	(45.20%)
Non-deductible transaction costs	0.50%	0.40%	(5.80%)
Non-recurring acquisition-related gain	0.00%	0.00%	31.10%
Valuation allowance	49.10%	(21.40%)	(101.00%)
Intangibles impairment	0.00%	0.00%	36.80%
Research and development credits	(15.00%)	(1.80%)	18.70%
Non-deductible acquisition-related charge	0.00%	0.00%	(6.20%)
Other	(9.80%)	6.10%	(4.60%)
Effective income tax rate	42.50%	2.50%	(2.90%)

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Acquisition Charge, Percent

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to non-recurring acquisition-related gain.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to non-deductible transaction cost.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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