Goodwill and Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019	Dec. 29, 2019
Acquired finite-lived intangible assets:
Gross Value	$ 143.2		$ 139.7
Accumulated Amortization	(109.1)		(107.1)
Net Value	34.1		32.6
Total intangible assets: gross value	150.1		146.6
Total intangible assets: net value	41.0		39.5
Aggregate amortization expense for finite-lived intangible assets	1.9	$ 1.5
Trade names
Acquired finite-lived intangible assets:
Indefinite-lived trade names	6.9		6.9
Customer relationships
Acquired finite-lived intangible assets:
Gross Value	73.0		72.3
Accumulated Amortization	(54.0)		(53.3)
Net Value	19.0		19.0
Contracts and backlog
Acquired finite-lived intangible assets:
Gross Value	32.7		32.0
Accumulated Amortization	(29.0)		(28.4)
Net Value	3.7		3.6
Developed technology and technical know-how
Acquired finite-lived intangible assets:
Gross Value	26.4		25.0
Accumulated Amortization	(24.4)		(23.8)
Net Value	2.0		1.2
Trade names
Acquired finite-lived intangible assets:
Gross Value	1.9		1.9
Accumulated Amortization	(1.7)		(1.6)
Net Value	0.2		0.3
In-process research and development
Acquired finite-lived intangible assets:
Gross Value	9.2		8.5
Accumulated Amortization	0.0		0.0
Net Value	$ 9.2		$ 8.5