Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	4 Months Ended	12 Months Ended
Dec. 30, 2017	Apr. 21, 2018	Apr. 22, 2017	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Effective tax rate		26.60%	36.50%
Corporate income tax rate		21.00%		35.00%
Income tax benefit recorded as estimate to the impact of the act	$ 48,200,000
Adjustments to estimate provisional income tax		$ 0

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB
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-SubTopic 10
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Amount 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 increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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