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Income Tax - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Dec. 29, 2018	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Income Tax Expense Benefit Continuing Operations [Line Items]
Federal statutory income tax rate			35.00%	35.00%	35.00%
Discrete income tax benefit due to tax act impact			$ 26.0
Effective rate			60.00%	36.60%	37.00%
Uncertain tax positions included in unrecognized tax benefits			$ 1.4
Forecast [Member]
Income Tax Expense Benefit Continuing Operations [Line Items]
Federal statutory income tax rate		21.00%
Impact of unrecognized tax benefits settlement on effective tax rate	$ 2.0
Forecast [Member] | Minimum [Member]
Income Tax Expense Benefit Continuing Operations [Line Items]
Effective rate		23.00%
Forecast [Member] | Maximum [Member]
Income Tax Expense Benefit Continuing Operations [Line Items]
Effective rate		24.00%

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Income tax expense benefit continuing operations.

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Tax cuts and Jobs act of 2017 change in tax rate income tax expense benefit.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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