Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue:
Net revenue	$ 53,165	$ 34,593	$ 114,812	$ 69,057
Cost of revenue:
Total cost of revenue	48,756	54,003	116,697	96,489
Gross profit (loss)	4,409	(19,410)	(1,885)	(27,432)
Operating expenses:
Research and development	8,402	7,436	25,477	20,059
Selling, general and administrative	8,652	9,535	29,202	36,584
Total operating expenses	17,054	16,971	54,679	56,643
Operating loss	(12,645)	(36,381)	(56,564)	(84,075)
Interest and other expense, net	(6,352)	(2,724)	(15,593)	(7,112)
Change in fair value of common stock warrant liability	1,716	(1,878)	3,308	(16,454)
Loss before income taxes	(17,281)	(40,983)	(68,849)	(107,641)
Income tax benefit	1,716		7,581
Net loss attributable to the Company	(15,565)	(40,983)	(61,268)	(107,641)
Preferred stock dividends declared and accretion of discount	(13)	(25)	(39)	(3,086)
Net loss attributable to common shareholders	$ (15,578)	$ (41,008)	$ (61,307)	$ (110,727)
Net loss per share:
Basic and diluted (in dollars per share)	$ (0.07)	$ (0.18)	$ (0.28)	$ (0.52)
Weighted average number of common shares outstanding	218,953,106	225,762,535	218,930,891	212,419,634
Sales of fuel cell systems and related infrastructure
Revenue:
Gross revenue	$ 36,668	$ 38,060	$ 66,101	$ 47,907
Cost of revenue:
Total cost of revenue	27,428	35,671	52,927	44,398
Services performed on fuel cell systems and related infrastructure
Revenue:
Gross revenue	5,156	2,217	16,330	10,496
Cost of revenue:
Total cost of revenue	5,302	4,531	17,139	14,684
Power purchase agreements
Revenue:
Gross revenue	5,555	(1,663)	16,365	7,593
Cost of revenue:
Total cost of revenue	8,767	7,853	27,055	21,844
Fuel delivered to customers
Revenue:
Gross revenue	5,786	(4,149)	16,016	2,782
Cost of revenue:
Total cost of revenue	$ 7,259	5,810	$ 19,576	15,262
Other
Revenue:
Gross revenue		128		279
Cost of revenue:
Total cost of revenue		$ 138		$ 301