Acquisitions (Narrative) (Details) (USD $)	6 Months Ended	1 Months Ended
Jun. 30, 2011	Jan. 31, 2011 BakBone Software Incorporated [Member]	Jan. 31, 2011 BakBone Software Incorporated [Member] IPR&D [Member]
Percentage of voting interest acquired		100.00%
Cash consideration paid		$ 56,000,000
Total purchase price	55,980,000
Discount rate used for valuation of intangible assets			28.00%
Goodwill allocation to licenses		45.00%
Goodwill allocation to services		52.00%
Goodwill allocation to professional services		3.00%
Additional acquisitions completed	three
Aggregate purchase price of other acquisitions	40,000,000
Preliminary allocation of purchase price to goodwill	20,000,000
Preliminary allocation of purchase price to intangibles	$ 21,000,000

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Discount rate used for valuation of in process research and development.

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+ 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph f(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

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