Goodwill and Other Intangible Assets (Details) (USD $) In Thousands	Sep. 24, 2011	Dec. 25, 2010
Goodwill
Gross Carrying Amount	$ 1,216,569	$ 1,216,196
Accumulated Amortization And Impairment Loss	(1,016,770)	(1,017,758)
Net Amount	199,799	198,438
Other intangible assets
Other intangible assets, Gross Carrying Amount	328,308	340,637
Other intangible assets, Accumulated Amortization & Impairment loss	(222,367)	(219,401)
Other intangible assets, Net Amount	105,941	121,236
Research models.
Other intangible assets not subject to amortization:
Other intangible assets not subject to amortization, Gross Carrying Amount	3,438	3,438
Other intangible assets not subject to amortization, Net Amount	3,438	3,438
PCS in process R&D
Other intangible assets not subject to amortization:
Other intangible assets not subject to amortization, Gross Carrying Amount	6,800	6,800
Other intangible assets not subject to amortization, Net Amount	6,800	6,800
Backlog
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	2,942	2,839
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(2,240)	(2,109)
Other intangible assets subject to amortization, Net Amount	702	730
Customer relationships
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	292,263	301,175
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(195,262)	(192,345)
Other intangible assets subject to amortization, Net Amount	97,001	108,830
Customer contracts
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	15,259	15,259
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(15,259)	(15,259)
Trademarks and trade names
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	4,649	5,041
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(4,649)	(4,614)
Other intangible assets subject to amortization, Net Amount		427
Standard operating procedures
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	657	657
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(657)	(657)
Other identifiable intangible assets
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, Gross Carrying Amount	4,300	5,428
Other intangible assets subject to amortization, Accumulated Amortization & Impairment loss	(4,300)	(4,417)
Other intangible assets subject to amortization, Net Amount		$ 1,011