Acquisitions - Schedule of Total Purchase Consideration (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	0 Months Ended
Mar. 31, 2014	Feb. 07, 2014 SkyFence Networks Ltd. [Member]
Business Acquisition [Line Items]
Cash	$ 12,083	$ 8,558
Cash holdback liability		7,157
Fair value of common stock		20,855
Estimated fair value of equity awards assumed and replaced		354
Total purchase price		$ 36,924

Business Acquisition Cost Of Acquired Entity Estimated Fair Value Of Stock Options Assumed

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- Definition

Business Acquisition Purchase Price Hold Back Liability

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

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-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

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- Definition

Fair value of equity issued in a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Paragraph 13

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