Indebtedness - Debt Extinguishment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Jul. 01, 2017	Dec. 31, 2015	Dec. 27, 2014	Dec. 31, 2017	Dec. 31, 2016	Jun. 27, 2015
Gains (Losses) on Extinguishment of Debt [Abstract]
Premium on debt repayment	$ 116.1
Transaction costs	3.8
Write-off of deferred financing fees	10.6
Write-off of unamortized discount	4.7
Total loss on extinguishment of debt	$ 135.2	$ 0.9	$ 9.6	$ 135.2	$ 1.1	$ 10.5