Severance (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Compensation Related Costs [Abstract]
Severance expense	$ 0	$ 1,800
Severance liability	1,100
Severance liability, current	$ 831		$ 1,564