Acquisitions - Pro Forma Financial Information (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended	0 Months Ended
Sep. 30, 2012	Sep. 25, 2011	Sep. 30, 2012	Sep. 25, 2011	Feb. 11, 2011 Herley Industries, Inc.	Jul. 27, 2011 Integral Systems, Inc.
Business Acquisition, Pro Forma Information [Abstract]
Pro forma revenues		$ 244.7	$ 752.8	$ 771.4
Pro forma net loss before tax		(32.4)	(27.0)	(60.3)
Net loss attributable to the registrant		(34.0)	(29.6)	(61.7)
Net income (loss) attributable to the registrant		(7.2)	(16.2)	(16.3)
Basic and diluted pro forma loss per share		$ (0.58)	$ (0.52)	$ (1.06)
Merger and acquisition expenses	$ 0.3	$ 3.7	$ 2.7	$ 11.3
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 Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 55

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph r(2, 3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 59

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