Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Mar. 28, 2020	Jun. 29, 2019
Income Tax Disclosure [Abstract]
Toll Tax Liability	$ 0.4	$ 0.8
Estimated Federal And State Income Taxes And Potential Withholding Taxes			$ 0.8
Foreign tax credits related to future repatriations of earnings		7.7
Gross potential research and development (R&D) tax credit		9.7
Unrecognized tax benefits associated with federal tax credits		4.2
Deferred Tax Assets, Tax Credit Carryforwards		$ 5.5

Estimated Federal And State Income Taxes And Potential Withholding Taxes

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- Definition

Toll Tax Liability

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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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 repatriation of foreign earnings.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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