Notes Payable - Energy Capital, LLC Loan (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 07, 2015
Long term debt
Proceeds from notes payable	$ 17,500
Amounts repaid under facility	12,500
Energy Capital Facility
Long term debt
Maximum amount available under facility		$ 10,000
Proceeds from notes payable	2,500
Amounts repaid under facility	$ 2,500