Nature of Business (Details) - USD ($) $ in Thousands	Aug. 12, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash and cash equivalents		$ 73,662	$ 73,849	$ 30,198	$ 9,709
Accumulated deficit		(148,885)	$ (103,595)
Period over which cash resources will be sufficient to allow Company to fund current operating plan	12 months
Note Agreement 1
Remaining borrowing capacity		$ 10,000