Quarterly report pursuant to Section 13 or 15(d)

Accounts Receivable and Concentration of Credit Risk (Narrative) (Details)

v3.21.1
Accounts Receivable and Concentration of Credit Risk (Narrative) (Details)
3 Months Ended 6 Months Ended 12 Months Ended
Mar. 31, 2021
customer
Mar. 31, 2020
customer
Mar. 31, 2021
USD ($)
customer
Mar. 31, 2020
USD ($)
item
Sep. 30, 2020
customer
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Change in allowance for doubtful accounts | $     $ 0 $ 0  
Minimum [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Credit terms     30 days    
Maximum [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Credit terms     120 days    
Assets, Current [Member] | Customer Concentration Risk [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Number of customers     0   0
Accounts Receivable [Member] | Customer Concentration Risk [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Number of customers     3   3
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Three Customers [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Concentration risk, percentage     81.00%   89.00%
Total Revenue [Member] | Customer Concentration Risk [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Number of customers 2 3 2 2  
Total Revenue [Member] | Customer Concentration Risk [Member] | Three Customers [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Concentration risk, percentage   80.00%      
Total Revenue [Member] | Customer Concentration Risk [Member] | Two Customers [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Concentration risk, percentage 77.00%   69.00% 71.00%  
Brazil [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Credit terms     90 days