Annual report pursuant to Section 13 and 15(d)

Investment Funds (Details)

v3.10.0.1
Investment Funds (Details)
$ in Thousands
Dec. 31, 2018
USD ($)
fund
Dec. 31, 2017
USD ($)
Variable Interest Entity [Line Items]    
Number of investment funds | fund 4  
Cash    
Variable Interest Entity [Line Items]    
Variable interest entity, assets $ 1,255 $ 444
Restricted cash    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 156 155
Accounts receivable    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 374 328
Costs and estimated earnings in excess of billings    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 498 360
Prepaid expenses and other current assets    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 190 8
Energy assets, net    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 122,641 55,712
Other assets    
Variable Interest Entity [Line Items]    
Variable interest entity, assets 1,613 1,398
Accounts payable    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities 234 764
Accrued liabilities    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities 4,146 74
Other liabilities    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities 0 75
Current portions of long-term    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities 1,712 0
Long-term debt, net of deferred financing costs    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities 26,461 0
Other long-term liabilities    
Variable Interest Entity [Line Items]    
Variable interest entity, liabilities $ 2,131 $ 0