Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 26, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax provision	$ 3,370	$ 198
Pre-tax income	$ 13,687	$ 3,300
Effective income tax rate	24.60%	6.00%
Discrete tax expense	$ 1,700
Statutory rate	21.00%		35.00%

Discrete net tax expense benefit.

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- Definition

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

+ References

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-Publisher FASB
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- Definition

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

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

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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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