Leases - Lease Expense (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Leases [Abstract]
Operating leases	[1]	$ 11.2		$ 23.2
Finance leases
Amortization		0.7		1.3
Interest		0.1		0.2
Total finance leases		$ 0.8		$ 1.5
Operating lease expense			$ 14.2		$ 26.1

[1] (a) Includes short-term leases and variable lease costs, which are immaterial.