Acquisitions - Additional Information (Detail) (USD $)	6 Months Ended		6 Months Ended
Jun. 30, 2012 Entity	Jun. 30, 2012 Bakbone Software Incorporated	Jan. 31, 2011 Bakbone Software Incorporated	Jun. 30, 2011 Other Acquisitions Entity
Business Acquisition
Total purchase price	$ 6,000,000	$ 55,980,000		$ 40,000,000
Allocation of purchase price to goodwill	2,700,000	18,690,000		20,000,000
Allocation of purchase price to intangible assets	3,800,000			20,000,000
Number acquisition that has been accounted for as a business combination	1			3
Percentage of voting interest acquired			100.00%
Cash consideration paid			$ 56,000,000
Discount rate used for valuation of intangible assets		28.00%
Goodwill allocation to Licenses		45.00%
Goodwill allocation to Maintenance Services		52.00%
Goodwill allocation to Professional Services		3.00%

Business acquisition, purchase price allocation, intangible assets

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- Definition

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

+ References

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- Definition

Percentage of goodwill allocation on licenses revenue

+ References

No definition available.

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- Definition

Percentage of goodwill allocation on maintenance services revenue

+ References

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- Definition

Percentage Of Goodwill Allocation On Profession Services Revenue

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- Definition

Amount of cash paid to acquire the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ 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

Percentage of voting equity interests acquired in the business combination.

+ 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 (c)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

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-Paragraph 68

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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.

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-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 Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

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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.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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