Performance-Based Common Stock Warrants Performance-Based Common Stock Warrants - (Details) - Common stock purchase warrant - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Class of Warrant or Right [Line Items]
Reduction/(increase) to net sales	$ (141)	$ 1,160	$ 1,122	$ 3,219
Income tax (benefit)/expense	$ 53	$ (426)	$ (418)	$ (1,182)