Income Taxes - Additional Information (Detail) - USD ($)	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018
Income Taxes [Line Items]
Corporate income tax rate	21.00%	21.00%
Excess tax benefit from stock-based awards	$ 2,968,000	$ 2,046,000
Estimated annual effective income tax rate	24.20%	24.50%
Effective income tax rate	22.80%	23.10%

Estimated Annual Effective Tax Rate For Continuing Operations

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- Definition

Income Taxes [Line Items]

+ References

No definition available.

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

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

+ References

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