Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

Document and Entity Information - shares
9 Months Ended
Dec. 31, 2020
Jan. 29, 2021
Entity Central Index Key 0001002135  
Current Fiscal Year End Date --03-31  
Amendment Flag false  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q3  
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Dec. 31, 2020  
Document Transition Report false  
Entity File Number 0-27266  
Entity Registrant Name Westell Technologies, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 36-3154957  
Entity Address, Address Line One 750 North Commons Drive  
Entity Address, City or Town Aurora  
Entity Address, State or Province IL  
Entity Address, Postal Zip Code 60504  
City Area Code 630  
Local Phone Number 898-2500  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Class A Common Stock    
Entity Common Stock, Shares Outstanding   7,521,271
Class B Common Stock    
Entity Common Stock, Shares Outstanding   3,484,287