Debt - Convertible Notes (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 17, 2014
Debt Instrument [Line Items]
Notes payable, principal		$ 9,505
Number of securities called by warrants (shares)		8,837,351			480,392
Loss on extinguishment of debt		$ 0	$ 82	$ 0
Interest expense		$ 800	100
Convertible Note Twenty Twelve
Debt Instrument [Line Items]
Interest rate					7.00%
Notes payable, principal					$ 1,225
Warrant exercise price (USD per share)					$ 2.55
Loss on extinguishment of debt	$ 100
Interest expense			$ 200	$ 500