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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Estimated amount of loss resulting from an adverse tax position.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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

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Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	Sep. 27, 2019	Sep. 28, 2018	Mar. 30, 2018	Sep. 27, 2019	Sep. 28, 2018	Dec. 28, 2018
Income Tax Contingency [Line Items]
Effective income tax rate	1.00%	(15.00%)		13.00%	6.00%
Statutory federal income tax rate				21.00%
Other Noncurrent Liabilities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits that would impact effective tax rate	$ 60.9			$ 60.9		$ 60.5
Unrecognized tax benefit liabilities include interest and penalties	$ 11.1			$ 11.1		$ 11.0
Tax Year 2010 and 2011 [Member] \| Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Proposed Adjustments on Income Tax Assessments			$ 51.2