GOODWILL AND INTANGIBLE ASSETS - Schedule of carrying amount of intangible assets (Details) - USD ($) $ in Thousands		12 Months Ended
	Feb. 23, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value			$ 361,302
Accumulated Amortization		$ (167,131)	(112,771)
Total		228,195	248,531
Indefinite-lived intangible assets			29,500
Intangible assets, Gross Carrying Value		395,326	390,802
Intangible assets, Net Carrying Value		228,195	278,031
Amortization expense of intangible assets		61,300	59,200	$ 10,100
Impairment of intangible assets		4,300
Licensed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		40,407	24,583
Accumulated Amortization		(16,478)	(6,559)
Total		23,929	18,024
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		279,543	250,043
Accumulated Amortization		(122,414)	(75,591)
Total		157,129	174,452
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	9 years
Gross Carrying Value		69,776	69,776
Accumulated Amortization		(24,783)	(17,731)
Total		$ 44,993	52,045
Backlog
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	1 year	1 year
Gross Carrying Value			11,300
Accumulated Amortization			(11,300)
Total			0
Trade names
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years	3 years
Gross Carrying Value		$ 5,600	5,600
Accumulated Amortization		(3,456)	(1,590)
Total		$ 2,144	$ 4,010
Minimum | Licensed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		1 year
Minimum | Developed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		4 years
Minimum | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		4 years
Maximum | Licensed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		8 years
Maximum | Developed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		7 years
Maximum | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life		9 years