Income Taxes - Summary (Details) $ in Millions	12 Months Ended
	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 31, 2016
Income Taxes
Federal statutory rate (as a percent)	21.00%	35.00%	35.00%
Decrease in effective tax rate due to changes in provisional amount	(6.2)
Benefit to the provisional amounts recorded at December 30, 2017	$ (4.5)
Transition tax cost		$ 54.4
Total provisional transaction tax liability		42.6
Decrease in provisional amount related to transition tax recorded at December 30, 2017	$ (6.1)
Period for payment of transition tax	8 years
Unpaid balance of its transition tax obligation payable between April 2022 and April 2025	$ 21.6
Net provisional benefit on remeasurement of certain deferred tax assets and liabilities		(28.1)
Increase in deferred tax expense due to revaluation of net deferred tax asset		21.8
Reduction in provisional tax benefit	$ 1.0
Altera decision
Income Taxes
Reversal of deferred tax liability		39.4
Reduction in deferred tax benefit due to reduction of corresponding deferred tax liability		$ 10.5