Income Taxes - Summary of Differences Between U.S. Federal Statutory Tax Rate and Company's Consolidated Effective Tax Rate (Detail)	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
U.S. federal statutory tax rate	21.00%	35.00%	21.00%	35.00%
State income taxes (net of federal benefit)	(0.60%)	0.50%	1.10%	1.50%
Cessation of operations	0.00%	0.00%	(0.90%)	(8.50%)
Research and development credit	(0.30%)	(2.10%)	(0.30%)	(2.20%)
Tax (windfall) shortfall on share-based awards	(3.00%)	(0.90%)	(12.40%)	0.00%
Tax return adjustments related to the 2017 Tax Act	(3.30%)	0.00%	(1.30%)	0.00%
Reserve for uncertain tax positions	(4.60%)	(4.50%)	(1.80%)	(1.70%)
Increase in valuation allowance due to net operating loss	(0.10%)	1.10%	0.20%	3.00%
Impact of Foreign Ops	4.20%	0.00%	3.20%	0.00%
Other	1.70%	1.40%	1.00%	(0.50%)
Total effective tax rate	15.00%	30.50%	9.80%	26.60%

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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Percentage 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 disposition of a business not qualifying as a discontinued operation.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Effective income tax rate reconciliation impact of foreign operations.

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Effective income tax rate reconciliation reserve for uncertain tax positions.

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Effective income tax rate reconciliation tax return adjustments related to 2017 tax act.

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