BALANCE SHEET INFORMATION - Schedule of Service Parts Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Mar. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Finished goods	$ 17,389	$ 18,773
Component parts	5,143	4,648
Total service parts inventories	$ 22,532	$ 23,421

Carrying amount of completed service parts merchandise or goods expected to be sold within one year or operating cycle, if longer.

No definition available.

Name:	qtm_ServicePartsInventoriesFinishedGoods
Namespace Prefix:	qtm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant