SEGMENT REPORTING AND GEOGRAPHIC INFORMATION SEGMENT REPORTING AND GEOGRAPHIC INFORMATION - Net Revenues by Major Product Category (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Apr. 03, 2021	Dec. 26, 2020	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Apr. 03, 2021	Mar. 28, 2020	Mar. 30, 2019
Revenue from External Customer [Line Items]
Net revenues	$ 476,233	$ 484,685	$ 410,969	$ 355,720	$ 403,043	$ 384,471	$ 461,709	$ 447,767	$ 1,727,607	$ 1,696,990	$ 1,674,535
Voice
Revenue from External Customer [Line Items]
Net revenues									221,131	375,505	344,586
Video
Revenue from External Customer [Line Items]
Net revenues									426,244	284,045	255,485
Service
Revenue from External Customer [Line Items]
Net revenues									$ 256,781	$ 264,254	$ 163,765