Goodwill and Intangible Assets - Purchased Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 24, 2012	Jun. 26, 2011	Jun. 24, 2012	Jun. 26, 2011	Dec. 25, 2011
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	$ 166.7		$ 166.7		$ 164.7
Accumulated Amortization	(84.0)		(84.0)		(64.6)
Net Value	82.7		82.7		100.1
Consolidated amortization expense related to intangible assets subject to amortization	8.9	9.2	19.4	12.6
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	79.2		79.2		78.1
Accumulated Amortization	(27.2)		(27.2)		(19.8)
Net Value	52.0		52.0		58.3
Contracts and backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	61.0		61.0		60.1
Accumulated Amortization	(50.3)		(50.3)		(39.6)
Net Value	10.7		10.7		20.5
Developed technology and technical know-how
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	22.1		22.1		22.1
Accumulated Amortization	(5.2)		(5.2)		(4.1)
Net Value	16.9		16.9		18.0
Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	2.6		2.6		2.6
Accumulated Amortization	(1.0)		(1.0)		(0.8)
Net Value	1.6		1.6		1.8
Indefinite-lived intangible assets	24.5		24.5		24.5
Favorable operating lease
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Value	1.8		1.8		1.8
Accumulated Amortization	(0.3)		(0.3)		(0.3)
Net Value	$ 1.5		$ 1.5		$ 1.5