Quarterly report pursuant to Section 13 or 15(d)

Investment Fund (Details)

v3.5.0.2
Investment Fund (Details) - USD ($)
$ in Thousands
Sep. 30, 2016
Dec. 31, 2015
Operating Cash    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets $ 949  
Restricted Cash    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 1,554 $ 5,419
Accounts Receivable    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 241  
Costs and Estimated Earnings in Excess of Billings    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 293  
Prepaid Expenses and Other Current Assets    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 43 25
Project Assets    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 32,535 32,657
Other Assets    
Variable Interest Entity [Line Items]    
Variable interest entity, carrying amount, assets 84 $ 112
Accrued Expenses and Other Current Liabilities    
Variable Interest Entity [Line Items]    
Variable interest entity, consolidated, carrying amount, liabilities $ 33