Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 30, 2017
Disclosure Income Taxes Additional Information [Abstract]
Tax Cuts and Jobs Act of 2017					$ 460.7
Income taxes on continuing operations	$ 1.0	$ 80.7	$ 82.7	$ 160.4
Document Period End Date			Jun. 30, 2018
Effective tax rate	0.30%	22.50%	15.10%	19.30%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount			$ 23.1
Business Combination, Acquisition Related Costs	7.00%	23.50%	13.40%	24.10%
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Provisional Income Tax Expense (Benefit)			$ 17.4		252.5
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax (Expense) Benefit					276.1
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit					184.6
Deferred Tax Liabilities, Gross, Noncurrent					$ 4.9