v3.26.1
Income Taxes - Narrative (Details) - USD ($)
$ in Thousands
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Tax Credit Carryforward [Line Items]      
Loss before income taxes $ (69,678) $ (51,411)  
Current state income tax expense 7 7  
Increase in valuation allowance $ 15,700 17,200  
Deferred tax assets, taxable income limitation 80.00%    
Unrecognized tax benefits $ 2,577 2,399 $ 4,931
Unrecognized tax benefits that would impact effective tax rate 0 0  
Interest or penalties related to unrecognized tax benefits 0 0  
Research and development      
Tax Credit Carryforward [Line Items]      
Unrecognized tax benefits 2,600 $ 2,400  
U.S. federal      
Tax Credit Carryforward [Line Items]      
Operating loss carryforwards 314,300    
Operating loss carryforwards, subject to expiration 80,600    
Operating loss carryforwards, not subject to expiration 233,700    
U.S. federal | Research and development      
Tax Credit Carryforward [Line Items]      
Tax credit carryforward 8,600    
State      
Tax Credit Carryforward [Line Items]      
Operating loss carryforwards, subject to expiration 63,700    
Operating loss carryforwards, not subject to expiration 10,800    
State | Research and development      
Tax Credit Carryforward [Line Items]      
Tax credit carryforward $ 2,200