Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Risk Concentrations - Revenue (Details)

v3.20.1
Summary of Significant Accounting Policies - Risk Concentrations - Revenue (Details) - Revenue from Contract with Customer Benchmark - Customer Concentration Risk
12 Months Ended
Mar. 31, 2020
Mar. 31, 2019
E-Finity    
Risk Concentrations    
Concentration percentage (as a percent) 12.00% 13.00%
Cal Microturbine    
Risk Concentrations    
Concentration percentage (as a percent) 12.00%