RESTRUCTURING AND OTHER RELATED CHARGES (CREDITS) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 10,633	$ 438	$ 10,633	$ 438
Restructuring and other related charges (credits)	7,261	$ (51)	8,581	2,522
Totals				4,300
Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			8,600	2,500
Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0	1,600
Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0	200
Severance Benefits from Reduction-In-Force [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				1,400
Severance Benefits from Reduction-In-Force [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				1,400
Severance Benefits from Reduction-In-Force [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Severance Benefits from Reduction-In-Force [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Lease Exit Charge and Asset Impairment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				700
Lease Exit Charge and Asset Impairment [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				700
Lease Exit Charge and Asset Impairment [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Lease Exit Charge and Asset Impairment [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Write-off of Unrecoverable Indirect Tax Asset in Brazil [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				700
Write-off of Unrecoverable Indirect Tax Asset in Brazil [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Write-off of Unrecoverable Indirect Tax Asset in Brazil [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				700
Write-off of Unrecoverable Indirect Tax Asset in Brazil [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Asset Impairments Related to Previous Clarity Operations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				400
Asset Impairments Related to Previous Clarity Operations [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				400
Asset Impairments Related to Previous Clarity Operations [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Asset Impairments Related to Previous Clarity Operations [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Loss on Clarity Asset Sale [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				900
Loss on Clarity Asset Sale [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Loss on Clarity Asset Sale [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				900
Loss on Clarity Asset Sale [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Accelerated Vesting of Restricted Stock [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				200
Accelerated Vesting of Restricted Stock [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Accelerated Vesting of Restricted Stock [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				0
Accelerated Vesting of Restricted Stock [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)				$ 200
Polycom Post-Acquisition Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			7,400
Polycom Post-Acquisition Plan [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			7,400
Polycom Post-Acquisition Plan [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Polycom Post-Acquisition Plan [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Polycom Acquired Restructuring Liability [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			(300)
Polycom Acquired Restructuring Liability [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			(300)
Polycom Acquired Restructuring Liability [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Polycom Acquired Restructuring Liability [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Plantronics Legacy Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			1,500
Plantronics Legacy Plan [Member] | Restructuring and Other Related Charges (Credits) [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			1,500
Plantronics Legacy Plan [Member] | Cost of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Plantronics Legacy Plan [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges (credits)			0
Polycom [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 8,200		$ 8,200