Power Plants - Schedule of Power Plants, Net (Details) $ in Thousands, ₨ in Millions	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 INR (₨)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Renewable energy facility [Line Items]
Total power plants in service, at cost	$ 1,486,483			$ 1,486,483		$ 1,449,758
Less: accumulated depreciation	(131,248)			(131,248)		(94,634)
Total power plants in service, net	1,355,235			1,355,235		1,355,124
Power plants, net	1,355,235			1,355,235		1,355,362
Land
Renewable energy facility [Line Items]
Total power plants in service, at cost	10,301			10,301		9,787
Solar power plants
Renewable energy facility [Line Items]
Total power plants in service, at cost	767,282			767,282		763,147
Wind power plants
Renewable energy facility [Line Items]
Total power plants in service, at cost	708,900			708,900		676,824
Construction in progress
Renewable energy facility [Line Items]
Power plants, net	0			0		$ 238
Power plants
Renewable energy facility [Line Items]
Depreciation	20,000	$ 12,100		$ 34,000	$ 25,800
Solar Energy Corporation of India (SECI) | India PSA
Renewable energy facility [Line Items]
Solar generation, conditional government subsidy | ₨			₨ 1,189.4
Solar generation, subsidy receipts, next twelve months, percentage			50.00%	50.00%		50.00%
Solar generation, subsidy receipts, each year for five years, percentage			10.00%	10.00%
Solar generation, subsidy receipts, year one, percentage			10.00%	10.00%
Viability Gap Funding subsidies						$ 8,900
Estimate of possible loss on terminated agreement under certain circumstances	3,100			$ 3,100
Solar Energy Corporation of India (SECI) | India PSA | Other current assets
Renewable energy facility [Line Items]
Solar generation, government subsidies receivable	2,400			2,400		2,300
Solar Energy Corporation of India (SECI) | India PSA | Other assets
Renewable energy facility [Line Items]
Solar generation, government subsidies receivable	$ 3,600			$ 3,600		$ 3,400