Nature of Operations - Description Of Business (Details)		3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($) agreement	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jul. 31, 2015 USD ($)	Dec. 31, 2012 USD ($)
Description of Business
Net loss attributable to common shareholders		$ 25,227,000	$ 10,238,000	$ 9,253,000	$ 11,077,000	$ 7,183,000	$ 9,377,000	$ (3,825,000)	$ 75,909,000	$ 55,795,000	$ 88,644,000	$ 62,791,000
Accumulated deficit	$ 993,876,000	993,876,000				938,081,000				993,876,000	938,081,000
Net cash used in operating activities										47,274,000	40,780,000	26,881,000
Net loss attributable to the Company										55,690,000	88,488,000	62,670,000
Net outflows of operating assets and liabilities										8,900,000
Cash and cash equivalents	63,961,000	63,961,000				146,205,000				63,961,000	146,205,000	$ 5,027,000		$ 9,380,000
Net working capital	$ 88,500,000	88,500,000				167,000,000				88,500,000	167,000,000
Number of power purchase agreements | agreement	7
Remaining lease payment	$ 60,282,000	60,282,000								60,282,000
Prepaid rent and security deposit	12,100,000	12,100,000				$ 0				12,100,000	$ 0
Power purchase agreements
Description of Business
Cash added to the restricted accounts										14,200,000
Remaining lease payment	26,100,000	26,100,000								26,100,000
Sale or leaseback agreements
Description of Business
Remaining lease payment	27,900,000	27,900,000								27,900,000
Prepaid rent and security deposit	12,100,000	12,100,000								12,100,000
Restricted cash	32,600,000	32,600,000								32,600,000
Master Lease
Description of Business
Minimum level of unrestricted cash										$ 50,000,000
Number of years that the underlying assets not be deployed										5 years
Residual exposure										$ 15,000,000
HyPulsion
Description of Business
Investment in equity	$ 0	$ 0								$ 0			$ 2,869,000
Axane, S.A. | HyPulsion
Description of Business
Ownership interest percentage													100.00%