Acquisitions - Pending Acquisitions Narrative (Details) $ in Thousands, ZAR in Millions	1 Months Ended		9 Months Ended			20 Months Ended
	Sep. 30, 2016 USD ($)	Apr. 30, 2015 power_plant MW shares	Sep. 30, 2016 USD ($) shares	Sep. 30, 2016 ZAR shares	Sep. 30, 2015 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2017 ZAR	Feb. 24, 2016 power_plant MW	Dec. 31, 2015 USD ($)	Aug. 31, 2015 USD ($) power_plant	Aug. 04, 2015 MW
Business Acquisition [Line Items]
Proceeds from Third Party Sale Transaction			$ 0		$ 9,305
BioTherm
Business Acquisition [Line Items]
Number of projects acquired | power_plant		3
Payments to acquire businesses			9,300
Escrow deposit	$ 43,900		43,900							$ 65,600
NPS Star
Business Acquisition [Line Items]
Number of projects acquired | power_plant								3
Capacity of acquired power plants | MW								17.8
WXA
Business Acquisition [Line Items]
Number of projects acquired | power_plant								3
Capacity of acquired power plants | MW								17.8
Non-current restricted cash | BioTherm
Business Acquisition [Line Items]
Cash deposits held for acquisitions									$ 20,300
Minority Interests in South African Acquisition [Member] | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses			6,500	ZAR 88.9
USD | BioTherm | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses			2,000
ZAR | BioTherm | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses			$ 800	ZAR 11.6
SunEdison | Del Litoral
Business Acquisition [Line Items]
Capacity of acquired power plants | MW											17.4
SunEdison | El Naranjal
Business Acquisition [Line Items]
Capacity of acquired power plants | MW											57.4
SunEdison | Bora Bora
Business Acquisition [Line Items]
Capacity of acquired power plants | MW											24.1
Common Stock | Deposits for acquisitions | BioTherm
Business Acquisition [Line Items]
Common stock issued in acquisition (in shares) | shares		544,055	544,055	544,055
Assets associated with Third Party Sale Transaction
Business Acquisition [Line Items]
Proceeds from Third Party Sale Transaction	$ 6,700		$ 6,700
South Africa | BioTherm
Business Acquisition [Line Items]
Number of projects acquired | power_plant		3								3
Capacity of acquired power plants | MW		32.6
Scenario, Forecast | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses						$ 74,900
Scenario, Forecast | USD | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses						67,600
Scenario, Forecast | ZAR | BioTherm
Business Acquisition [Line Items]
Payments to acquire businesses						$ 7,300	ZAR 100.4