Quarterly report pursuant to Section 13 or 15(d)

Customer Concentrations and Accounts Receivable - Customer Concentrations (Details)

v3.19.2
Customer Concentrations and Accounts Receivable - Customer Concentrations (Details)
3 Months Ended 12 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Mar. 31, 2019
Revenue | Customer concentrations | E-Finity      
Customer Concentrations and Accounts Receivable      
Concentration percentage 12.00% 10.00%  
Revenue | Customer concentrations | Cal      
Customer Concentrations and Accounts Receivable      
Concentration percentage 10.00%    
Revenue | Customer concentrations | CAT      
Customer Concentrations and Accounts Receivable      
Concentration percentage   18.00%  
Revenue | Customer concentrations | Supernova      
Customer Concentrations and Accounts Receivable      
Concentration percentage   12.00%  
Net accounts receivable | Credit concentration | E-Finity      
Customer Concentrations and Accounts Receivable      
Concentration percentage     10.00%
Net accounts receivable | Credit concentration | Innovative Energy Company Limited      
Customer Concentrations and Accounts Receivable      
Concentration percentage 12.00%    
Net accounts receivable | Credit concentration | DTC      
Customer Concentrations and Accounts Receivable      
Concentration percentage 11.00%    
Net accounts receivable | Credit concentration | Reliable Secure Power Systems      
Customer Concentrations and Accounts Receivable      
Concentration percentage     14.00%