Pension Plans Components of Net Periodic Pension Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
United States Pension Plan of US Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 0.3	$ 0.0
Expected return on plan assets	(0.4)	0.0
Net periodic pension cost	(0.1)	0.0
Foreign Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	1.0
Interest cost	1.5	1.4
Expected return on plan assets	(1.9)	(1.8)
Amortization of net loss	0.9	1.1
Net periodic pension cost	$ 1.0	$ 1.7