Income Taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Solar investment tax credit	$ 2,116	$ 2,116
Federal and state net operating loss	2,131	2,284
Other	22	22
Less: valuation allowance	(3,849)	(4,002)
Total deferred tax assets	420	420
Deferred tax liabilities:
Deferred revenue	0	0
Depreciation and amortization	(420)	(420)
Total deferred tax liabilities	(420)	(420)
Net deferred tax assets	$ 0	$ 0