Quarterly report pursuant to Section 13 or 15(d)

Debt - Additional Information (Details)

v3.20.2
Debt - Additional Information (Details)
1 Months Ended 3 Months Ended
Feb. 29, 2020
Jul. 31, 2020
USD ($)
Jun. 30, 2020
USD ($)
May 31, 2020
USD ($)
bank
Apr. 30, 2020
USD ($)
project
Mar. 31, 2020
USD ($)
Jun. 30, 2020
USD ($)
project
Sep. 30, 2020
USD ($)
Energy Project                
Debt Instrument [Line Items]                
Number of projects acquired | project             1  
Fixed Rate Loan due April 2040                
Debt Instrument [Line Items]                
Long-term debt               $ 218,000
Line of Credit | Revolving Credit Facility                
Debt Instrument [Line Items]                
Total funded debt to EBITDA covenant ratio, maximum           3.75    
Long-term debt           $ 185,000,000    
Funds available for borrowing               45,668,000
Line of Credit | Revolving Credit Facility | Revolving Credit Agreement                
Debt Instrument [Line Items]                
Debt instrument, number of banks | bank       2        
Maximum borrowing capacity       $ 41,850,000        
Increase in interest rate       0.125%        
Period for increase in interest rate       3 years        
Line of credit               39,936,000
Line of Credit | Revolving Credit Facility | Construction Revolver Loans Payable Due In November 2020                
Debt Instrument [Line Items]                
Maximum borrowing capacity     $ 100,000,000       $ 100,000,000  
Line of credit               7,564,000
Line of Credit | Revolving Credit Facility | Construction Revolver Loans Payable Due In July 2022                
Debt Instrument [Line Items]                
Funds available for borrowing               18,956,000
Maximum borrowing capacity   $ 30,000,000            
Line of credit               $ 10,659,000
Line of Credit | Revolving Credit Facility | Eurocurrency Rate                
Debt Instrument [Line Items]                
Basis spread on variable rate 0.00%         1.00%    
Line of Credit | Revolving Credit Facility | LIBOR | Revolving Credit Agreement                
Debt Instrument [Line Items]                
Basis spread on variable rate       2.25%        
Line of Credit | Revolving Credit Facility | LIBOR | Construction Revolver Loans Payable Due In November 2020                
Debt Instrument [Line Items]                
Basis spread on variable rate     1.50%          
Line of Credit | Revolving Credit Facility | LIBOR | Construction Revolver Loans Payable Due In July 2022                
Debt Instrument [Line Items]                
Basis spread on variable rate   1.75%            
Borrowing capacity Increase limit   $ 20,000,000            
Line of Credit | Revolving Credit Facility | Base Rate | Construction Revolver Loans Payable Due In November 2020                
Debt Instrument [Line Items]                
Basis spread on variable rate     0.50%          
Loans Payable | Fixed Rate Loan due April 2040                
Debt Instrument [Line Items]                
Original principal amount         $ 218,000      
Fixed interest rate, percentage         5.00%     5.00%
Loans Payable | Fixed Rate Loan due April 2040 | Energy Project                
Debt Instrument [Line Items]                
Number of projects acquired | project         1