Bonus depreciation on assets, threshold percentage.

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- Definition

Current deductibility of net interest expense on adjusted taxable income, threshold percentage.

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No definition available.

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Income Taxes [Line Items]

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Net operating losses on taxable income, threshold percentage.

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No definition available.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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No definition available.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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

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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended
	Apr. 28, 2018	Jan. 27, 2018	Jan. 28, 2017	Jan. 27, 2018	Jan. 28, 2017
Income Taxes [Line Items]
Income (loss) before taxes		$ (37,411,000)	$ 126,711,000	$ (109,573,000)	$ 72,467,000
Income taxes benefit		$ 26,125,000	$ 56,435,000	$ (5,165,000)	$ 37,016,000
Effective income tax rate		(69.80%)	44.50%	4.70%	51.10%
Amount of unrecognized tax benefits reasonably possible		$ 863,000		$ 863,000
Corporate tax rate		3500.00%
US income tax expense (benefit), continuing operations, adjustment of deferred tax (asset) liability		$ 26,403
Current deductibility of net interest expense on adjusted taxable income, threshold percentage				30.00%
Net operating losses on taxable income, threshold percentage				80.00%
Bonus depreciation on assets, threshold percentage				100.00%
Deferred tax assets, valuation allowance		34,979,000		$ 34,979,000
Scenario Forecast
Income Taxes [Line Items]
Corporate tax rate	2100.00%
ASU 2016-09
Income Taxes [Line Items]
Excess tax benefits on share based payments		$ 11,000		$ 915,000