Summary of Significant Accounting Policies (Property) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Property and Equipment
Estimated useful life				P3Y
Net loss	$ (19,681)		$ (514)	$ (29,685)	$ (10,130)
Basic and diluted (in dollars per share)	$ (3.58)		$ (0.11)	$ (5.50)	$ (2.17)
Machinery and equipment | Change to estimated useful life
Property and Equipment
Estimated useful life	P5Y	P3Y
Net loss	$ 600			$ 600
Basic and diluted (in dollars per share)	$ 0.11			$ 0.12