Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Apr. 01, 2016	Dec. 30, 2016
Income Tax Contingency [Line Items]
Effective income tax rate	23.00%	33.00%
Statutory federal income tax rate	35.00%	35.00%
Unrecognized tax benefits that would impact effective tax rate	$ 62.6		$ 60.5
Unrecognized tax benefit liabilities include interest and penalties	9.9		9.3
Tax Year 2010 and 2011 [Member] \| Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Proposed Adjustments on Income Tax Assessments	67.0
Written proposal to IRS assessment			$ 15.8
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 6.2

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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-Name Accounting Standards Codification
-Topic 740
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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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Estimated amount of loss resulting from an adverse tax position.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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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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