Acquisitions - Pro Forma Financial Information (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended	0 Months Ended
Dec. 30, 2012	Dec. 25, 2011	Feb. 11, 2011 Herley Industries, Inc.	Jul. 27, 2011 Integral Systems, Inc.
Business Acquisition, Pro Forma Information [Abstract]
Pro forma revenues	$ 1,019.5	$ 1,046.9
Pro forma net loss before tax	(132.0)	(63.6)
Pro forma net loss	(130.4)	(67.1)
Net loss attributable to the registrant	$ (112.9)	$ (23.5)
Basic and diluted pro forma loss per share (in dollars per share)	$ (2.31)	$ (1.15)
Common stock issued in acquisition, shares			4.9	10.4

Business Acquisition Pro Forma Income (Loss) From Continuing Operations Before Income Taxes

No definition available.

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- Definition

Business Acquisition, Pro Forma Net Income (Loss) Attributable to Parent

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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