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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. 29, 2017	Sep. 30, 2016	Apr. 03, 2015	Sep. 29, 2017	Sep. 30, 2016	Dec. 30, 2016
Income Tax Contingency [Line Items]
Effective income tax rate	20.00%	25.00%		23.00%	21.00%
Statutory federal income tax rate				35.00%	35.00%
Unrecognized tax benefits that would impact effective tax rate	$ 70.9			$ 70.9		$ 60.5
Unrecognized tax benefit liabilities include interest and penalties	10.6			10.6		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			$ 6.2