Acquisitions (Allocation Of Purchase Price To Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2011 years
BakBone Software Incorporated [Member]
Current assets	$ 12,479
Goodwill	20,730
Deferred income tax assets (liabilities) - non-current	7,832
Other assets	2,419
Current liabilities	(6,328)
Deferred revenue - current	(9,383)
Deferred revenue - non-current	(9,491)
Other long-term liabilities	(278)
Total purchase price	55,980
BakBone Software Incorporated [Member] \| Acquired Technologies [Member]
Amortizable intangible assets	24,500
Useful life of amortizable intangible assets (years)	5.2
BakBone Software Incorporated [Member] \| IPR&D [Member]
Amortizable intangible assets	400
BakBone Software Incorporated [Member] \| Customer Relationships [Member]
Amortizable intangible assets	11,300
Useful life of amortizable intangible assets (years)	4.0
BakBone Software Incorporated [Member] \| Trademarks And Trade Names [Member]
Amortizable intangible assets	1,800
Useful life of amortizable intangible assets (years)	10.0
Volcker Informatik AG [Member]
Current assets	2,823
Goodwill	13,930
Deferred income tax assets (liabilities) - non-current	(2,645)
Other assets	490
Current liabilities	(1,246)
Total purchase price	22,169
Volcker Informatik AG [Member] \| Acquired Technologies [Member]
Amortizable intangible assets	5,416
Useful life of amortizable intangible assets (years)	4.5
Volcker Informatik AG [Member] \| Customer Relationships [Member]
Amortizable intangible assets	3,401
Useful life of amortizable intangible assets (years)	4.5
Surgient, Inc [Member]
Current assets	789
Goodwill	26,011
Deferred income tax assets (liabilities) - non-current	9,178
Other assets	1,271
Deferred revenue - current	(2,943)
Other current liabilities	(1,124)
Deferred revenue - non-current	(572)
Total purchase price	35,000
Surgient, Inc [Member] \| Acquired Technologies [Member]
Amortizable intangible assets	1,030
Useful life of amortizable intangible assets (years)	3.5
Surgient, Inc [Member] \| Customer Relationships [Member]
Amortizable intangible assets	1,240
Useful life of amortizable intangible assets (years)	3.5
Surgient, Inc [Member] \| IPR&D [Member]
Amortizable intangible assets	$ 120

The amount of acquisition cost of a business combination allocated to non-current deferred revenue of the acquired entity.

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- Definition

The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 44

-Subparagraph a(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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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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

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to current assets.

+ References

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to current liabilities of the acquired 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 e

-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 37

-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 Emerging Issues Task Force (EITF)

-Number 98-1

-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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- Definition

The amount of acquisition cost of a business combination allocated to deferred revenue of the acquired entity.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 01-3

-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 amount of acquisition cost of a business combination allocated to other current liabilities of the acquired entity. Does not include amounts allocated to the current portion of long-term debt, accounts payable and accrued expenses.

+ References

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- Definition

Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

+ References

+ Details

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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

-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 amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-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 Emerging Issues Task Force (EITF)

-Number 98-1

-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.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph f

-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 amount of acquisition cost of a business combination allocated to other noncurrent liabilities of the acquired entity.

+ References

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