Summary of Significant Accounting Policies (Property) (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Apr. 30, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property and Equipment
Estimated useful life										P3Y
Gain (loss) from operations										$ (59,838)	$ 665	$ (25,268)
Net loss		$ 22,960	$ 17,630	$ 19,681	$ 10,004	$ (1,254)	$ (3,724)	$ 514	$ 9,616	$ 70,275	$ 5,152	$ 37,110
Basic and diluted net loss per share (in dollars per share)		$ (0.47)	$ (0.39)	$ (3.58)	$ (1.89)					$ (2.68)	$ (1.07)	$ (9.66)
Machinery and equipment | Change to estimated useful life
Property and Equipment
Estimated useful life	P3Y									P5Y
Net loss										$ 1,700
Basic and diluted net loss per share (in dollars per share)										$ (0.07)