Pension Plans Components of Net Periodic Pension Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 28, 2018	Sep. 29, 2017
Domestic Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 0.3	$ 0.0	$ 0.9	$ 0.0
Expected return on plan assets	(0.4)	0.0	(1.1)	0.0
Net periodic pension cost	(0.1)	0.0	(0.2)	0.0
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	1.1	1.4	3.1
Interest cost	1.4	1.5	4.4	4.4
Expected return on plan assets	(1.8)	(1.9)	(5.5)	(5.5)
Amortization of net loss	0.9	1.2	2.7	3.4
Net curtailment and settlement loss recognized	0.3	0.0	0.9	0.0
Net periodic pension cost	$ 1.3	$ 1.9	$ 3.9	$ 5.4