Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Automotive sales	$ 3,192,723	$ 1,997,786	$ 385,699
Development services	5,633	15,710	27,557
Total revenues	3,198,356	2,013,496	413,256
Cost of revenues
Automotive sales	2,310,011	1,543,878	371,658
Development services	6,674	13,356	11,531
Total cost of revenues	2,316,685	1,557,234	383,189
Gross profit	881,671	456,262	30,067
Operating expenses
Research and development	464,700	231,976	273,978
Selling, general and administrative	603,660	285,569	150,372
Total operating expenses	1,068,360	517,545	424,350
Loss from operations	(186,689)	(61,283)	(394,283)
Interest income	1,126	189	288
Interest expense	(100,886)	(32,934)	(254)
Other income (expense), net	1,813	22,602	(1,828)
Loss before income taxes	(284,636)	(71,426)	(396,077)
Provision for income taxes	9,404	2,588	136
Net loss	$ (294,040)	$ (74,014)	$ (396,213)
Net loss per share of common stock, basic and diluted	$ (2.36)	$ (0.62)	$ (3.69)
Weighted average shares used in computing net loss per share of common stock, basic and diluted	124,539,343	119,421,414	107,349,188