10. Project Assets (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Project assets	$ 41,022	$ 58,579
Revenues	125,582	121,520	$ 114,602
Cost of revenue	114,525	111,428	102,532
PV project assets and pre-development solar projects [Member]
Revenues	26,603	6,042	14,914
Cost of revenue	23,418	6,229	13,613
Certain project assets [Member]
Project impairment loss	0	687	13,102
UNITED STATES
Project assets	31,170	42,990
Revenues	18,721	0	6,622
JAPAN
Project assets	9,852	15,589
Revenues	$ 12,437	$ 511	$ 12,893

Project assets costs consist primarily of capitalizable costs for items such as permits and licenses, acquired land or land use rights, and work-in-process.

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The aggregate cost of goods produced and sold and services rendered during the reporting period.

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Amount recognized as an operating expense or loss during the period to reduce the carrying amount of a project that has been impaired but not abandoned.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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