Segment Information - Reconciliation of reportable segments' assets to consolidated total assets (Details 1) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 22,703	$ 34,245
Continuing Operations
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	18,543	24,736
Continuing Operations | Residential
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	13,351	16,322
Continuing Operations | Sunetric
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	4,566	7,430
Continuing Operations | Other
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	626	984
Discontinued Operations | Commercial Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 4,160	$ 9,509