Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Variable-Rate Construction and Term Loans (Details)

v3.8.0.1
Long-Term Debt - Variable-Rate Construction and Term Loans (Details)
1 Months Ended
Jan. 31, 2017
USD ($)
project
Dec. 31, 2016
USD ($)
Sep. 30, 2017
USD ($)
Jun. 30, 2017
USD ($)
Apr. 30, 2017
USD ($)
Mar. 31, 2017
USD ($)
Nov. 30, 2016
USD ($)
Aug. 31, 2016
USD ($)
bank
Sep. 30, 2015
USD ($)
Debt Instrument [Line Items]                  
Long-term debt     $ 202,297,000            
Number of projects acquired | project 2                
Term Loan                  
Debt Instrument [Line Items]                  
Weighted average interest rate     3.32%            
Number of banks | bank               2  
Term Loan | 2015 Variable Rate Construction Term Loan                  
Debt Instrument [Line Items]                  
Original principal amount                 $ 20,746,000
Term Loan | 2015 Variable Rate Term Loan                  
Debt Instrument [Line Items]                  
Debt outstanding   $ 19,877,000 $ 19,471,000            
Weighted average interest rate     3.83%            
Term Loan | Fixed Rate Construction Term Loan                  
Debt Instrument [Line Items]                  
Original principal amount               $ 4,837,000  
Debt outstanding   4,616,000 $ 4,742,000            
Fixed interest rate               4.95%  
Term Loan | 8.750% Loan                  
Debt Instrument [Line Items]                  
Original principal amount             $ 9,500,000    
Debt outstanding   3,258,000 5,126,000            
Fixed interest rate             8.75%    
Term Loan | Variable Rate Loan                  
Debt Instrument [Line Items]                  
Original principal amount             $ 35,000,000    
Long-term debt   7,008,000 $ 4,516,000            
Effective interest rate     6.75%            
Term Loan | 13% Loan                  
Debt Instrument [Line Items]                  
Original principal amount   $ 10,694,000              
Fixed interest rate   13.00%              
Long-term debt   $ 9,503,000              
Subjective acceleration clause, repayment period   60 days              
Term Loan | 13% Loan, Facility One                  
Debt Instrument [Line Items]                  
Original principal amount $ 3,823,000                
Fixed interest rate 13.00%                
Subjective acceleration clause, repayment period 60 days                
Term Loan | 13% Loan, Facility Two                  
Debt Instrument [Line Items]                  
Original principal amount $ 4,008,000                
Fixed interest rate   13.00%              
Subjective acceleration clause, repayment period 60 days                
Term Loan | Fixed Rate Construction Term Loan 2017                  
Debt Instrument [Line Items]                  
Original principal amount           $ 4,300,000      
Debt outstanding     $ 4,092,000            
Term Loan | Fixed Rate Construction Term Loan 2017, Construction Phase                  
Debt Instrument [Line Items]                  
Fixed interest rate           5.50%      
Term Loan | Fixed Rate Construction Term Loan 2017, Term Loan Phase                  
Debt Instrument [Line Items]                  
Fixed interest rate           5.00%      
Term Loan | Non-Recourse Construction Term Loan - Biogas Facility Project                  
Debt Instrument [Line Items]                  
Debt outstanding     13,325,000            
Fixed interest rate         4.50%        
Construction loan         $ 24,823,000        
Term Loan | Limited Recourse Construction Term Loan                  
Debt Instrument [Line Items]                  
Original principal amount         $ 3,151,000        
Debt outstanding     3,193,000            
Fixed interest rate         5.61%        
Term Loan | Variable Rate Construction Term Loan 2017                  
Debt Instrument [Line Items]                  
Original principal amount       $ 14,100,000          
Debt outstanding     $ 14,100,000            
Weighted average interest rate     3.77%            
Term Loan | Non-Recourse Construction Term Loan - Solar PV Project                  
Debt Instrument [Line Items]                  
Debt outstanding     $ 747,000            
Fixed interest rate     4.25%            
Construction loan     $ 3,126,000