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Commitments and Contingencies - Additional Information (Detail) € in Millions	1 Months Ended		3 Months Ended
	Jun. 30, 2012 Patents	Oct. 30, 2011 Patents	Sep. 30, 2016 USD ($)	Jul. 01, 2016 USD ($)	Apr. 01, 2016 USD ($)	Feb. 29, 2016 USD ($)	Feb. 29, 2016 EUR (€)
Other Commitments [Line Items]
Non-cancelable purchase commitments			$ 21,700,000
Maximum amount of potential future payments under the company's financial guarantees			700,000
Business Acquisition, Preacquisition Contingency, Amount of Settlement			2,500,000	$ 3,500,000
Business Combination, Contingent Consideration, Liability, Current			0
Loss Contingency, Patents Allegedly Infringed, Number \| Patents	1	2
Guarantee Obligations [Member]
Other Commitments [Line Items]
Guarantees related to rent obligations			1,900,000
Indemnification [Member]
Other Commitments [Line Items]
Accrual for indemnification provisions			0
Israel [Member] \| Guarantee Obligations [Member]
Other Commitments [Line Items]
Guarantees related to rent obligations			400,000
TVN [Member] \| Guarantee Obligations [Member]
Other Commitments [Line Items]
Guarantees related to rent obligations			1,300,000
TVN [Member]
Other Commitments [Line Items]
Business Combination, Contingent Consideration, Liability			0
Business Combination, Contingent Consideration, Liability, Current					$ 8,000,000
TVN's 2015 revenue, difference as converted from euros to US dollars [Member] \| TVN [Member]
Other Commitments [Line Items]
Business Combination, Contingent Consideration, Liability						$ 75,000,000
TVN's 2015 revenue, difference as converted from euros to US dollars [Member] \| Maximum [Member] \| TVN [Member]
Other Commitments [Line Items]
Business Combination, Contingent Consideration, Liability						83,300,000	€ 76
TVN's 2015 backlog [Member] \| Maximum [Member] \| TVN [Member]
Other Commitments [Line Items]
Business Combination, Contingent Consideration, Liability						$ 5,000,000
Cash Earnout [Member] \| TVN [Member]
Other Commitments [Line Items]
Other Payments to Acquire Businesses			$ 2,500,000	$ 3,500,000