ACQUISITION, GOODWILL, AND ACQUIRED INTANGIBLE ASSETS ACQUISITION, GOODWILL, AND ACQUIRED INTANGIBLE ASSETS - Acquired Intangible Assets (Details) - USD ($) $ in Thousands		3 Months Ended
	Jul. 02, 2018	Jun. 30, 2019	Mar. 31, 2019
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization		$ 177,446	$ 132,179
Finite-Lived Intangible Assets, Net		780,348
Polycom [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 927,400
Amortization of Intangible Assets		$ 45,300
Weighted Average Remaining Useful Life		5 years 5 months 12 days
Intangible Assets Acquired	985,400
Existing technology
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization		$ 116,295	86,301
Weighted Average Remaining Useful Life		4 years
Existing technology | Polycom [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	538,600
Weighted Average Remaining Useful Life		4 years 11 months 12 days
Customer relationships
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization		$ 48,306	$ 36,245
Weighted Average Remaining Useful Life		4 years 7 months 6 days
Customer relationships | Polycom [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	245,100
Weighted Average Remaining Useful Life		5 years 5 months 15 days
Order or Production Backlog [Member] | Polycom [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	28,100
Weighted Average Remaining Useful Life		7 days
Trademarks and Trade Names [Member]
Business Acquisition [Line Items]
Weighted Average Remaining Useful Life		8 years
Trademarks and Trade Names [Member] | Polycom [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	115,600
Weighted Average Remaining Useful Life		9 years
In-process R&D | Polycom [Member]
Business Acquisition [Line Items]
Indefinite-lived Intangible Assets Acquired	$ 58,000