DOCUMENT AND ENTITY INFORMATION - shares	6 Months Ended
	Sep. 30, 2018	Nov. 02, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	PLANTRONICS INC /CA/
Entity Central Index Key	0000914025
Current Fiscal Year End Date	--03-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		39,803,774