Goodwill and Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 27, 2016	Mar. 29, 2015	Dec. 27, 2015
Acquired finite-lived intangible assets:
Gross Value	$ 108.2		$ 185.2
Accumulated Amortization	(81.3)		(155.6)
Net Value	26.9		29.6
Total intangible assets: Gross Value	115.1		192.1
Total intangible assets: Net Value	33.8		36.5
Aggregate amortization expense for finite-lived intangible assets	2.7	$ 3.7
Trade names
Acquired finite-lived intangible assets:
Indefinite-lived trade names	6.9		6.9
Customer relationships
Acquired finite-lived intangible assets:
Gross Value	57.1		83.7
Accumulated Amortization	(42.4)		(67.1)
Net Value	14.7		16.6
Contracts and backlog
Acquired finite-lived intangible assets:
Gross Value	24.8		71.3
Accumulated Amortization	(23.1)		(69.4)
Net Value	1.7		1.9
Developed technology and technical know-how
Acquired finite-lived intangible assets:
Gross Value	23.1		23.1
Accumulated Amortization	(13.9)		(13.3)
Net Value	9.2		9.8
Trade names
Acquired finite-lived intangible assets:
Gross Value	1.4		5.3
Accumulated Amortization	(1.0)		(4.9)
Net Value	0.4		0.4
Favorable operating lease
Acquired finite-lived intangible assets:
Gross Value	1.8		1.8
Accumulated Amortization	(0.9)		(0.9)
Net Value	$ 0.9		$ 0.9