LICENSE, SETTLEMENT AND RELEASE AGREEMENT (Details) $ in Thousands									3 Months Ended		6 Months Ended
	Jun. 29, 2018 USD ($) asset	Apr. 09, 2018 USD ($)	Apr. 06, 2018 installment_payment	Mar. 19, 2018 USD ($)	Feb. 28, 2018 USD ($)	Feb. 01, 2018 USD ($)	Apr. 21, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2019 USD ($)	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Finite-Lived Intangible Assets [Line Items]
License revenue									$ 17,300	$ 2,309	$ 82,300	$ 27,056
Licensing Agreements | Trend Micro Parties
Finite-Lived Intangible Assets [Line Items]
Number of assets transferred | asset	18
Litigation Settlement, Amount Awarded from Other Party	$ 13,400
Licensing Agreements | Carbon Black, Inc
Finite-Lived Intangible Assets [Line Items]
Cash received from license agreement		$ 1,300									3,900
Payment period			5 days
Percentage of gross revenue			8.00%
Number of quarterly installments | installment_payment			4
Licensing Agreements | Carbon Black, Inc | Forecast
Finite-Lived Intangible Assets [Line Items]
Receivable related to license agreement															$ 1,300	$ 1,300
Licensing Agreements | Symantec Corp
Finite-Lived Intangible Assets [Line Items]
Litigation Settlement, Amount Awarded from Other Party				$ 65,000
Payment period					20 days
Payable period of agreement					4 years
Licensing Agreements | EU Licensee
Finite-Lived Intangible Assets [Line Items]
Cash received from license agreement											2,300
Litigation Settlement, Amount Awarded from Other Party							$ 4,900
Payment period							10 days
Receivable related to license agreement						$ 1,300	$ 2,300
Licensing Agreements | EU Licensee | Forecast
Finite-Lived Intangible Assets [Line Items]
Receivable related to license agreement														$ 1,300
Licensing Agreements | Sophos Group
Finite-Lived Intangible Assets [Line Items]
Cash received from license agreement								$ 15,000
Receivable related to license agreement									$ 2,500		2,500						$ 1,250
Licensing Agreements | Sophos Group | Forecast
Finite-Lived Intangible Assets [Line Items]
Receivable related to license agreement													$ 1,250
Maximum | Licensing Agreements | Symantec Corp
Finite-Lived Intangible Assets [Line Items]
Additional license fees					$ 45,000
License | Licensing Agreements | Carbon Black, Inc
Finite-Lived Intangible Assets [Line Items]
License revenue											$ 3,900
License | Licensing Agreements | Symantec Corp
Finite-Lived Intangible Assets [Line Items]
License revenue					$ 65,000
License | Licensing Agreements | EU Licensee
Finite-Lived Intangible Assets [Line Items]
License revenue						$ 1,300
License | Licensing Agreements | Sophos Group
Finite-Lived Intangible Assets [Line Items]
License revenue								$ 15,000