Goodwill and Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 27, 2022	Mar. 28, 2021	Dec. 26, 2021
Acquired finite-lived intangible assets:
Gross Value	$ 165.0		$ 155.0
Accumulated Amortization	(120.4)		(118.7)
Net Value	44.6		36.3
Total intangible assets: gross value	171.9		161.9
Total intangible assets: net value	51.5		43.2
Aggregate amortization expense for finite-lived intangible assets	1.7	$ 1.4
Trade names
Acquired finite-lived intangible assets:
Indefinite-lived trade names	6.9		6.9
Customer relationships
Acquired finite-lived intangible assets:
Gross Value	79.0		76.5
Accumulated Amortization	(58.2)		(57.6)
Net Value	20.8		18.9
Contracts and backlog
Acquired finite-lived intangible assets:
Gross Value	37.9		34.9
Accumulated Amortization	(33.8)		(33.1)
Net Value	4.1		1.8
Developed technology and technical know-how
Acquired finite-lived intangible assets:
Gross Value	34.4		31.4
Accumulated Amortization	(26.1)		(25.8)
Net Value	8.3		5.6
Trade names
Acquired finite-lived intangible assets:
Gross Value	4.2		2.7
Accumulated Amortization	(2.1)		(2.0)
Net Value	2.1		0.7
In-process research and development
Acquired finite-lived intangible assets:
Gross Value	9.5		9.5
Accumulated Amortization	(0.2)		(0.2)
Net Value	$ 9.3		$ 9.3