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

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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.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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

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-Glossary Investing Activities

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Acquisitions - Schedule of Total Purchase Consideration (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 07, 2014
Business Acquisition [Line Items]
Cash	$ 12,083	$ 0	$ 0
Skyfence Networks Ltd. [Member]
Business Acquisition [Line Items]
Cash				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