Stockholders' Equity and Redeemable Convertible Preferred Stock (Details 3) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Total compensation expense	$ 8	$ 167	$ 11	$ 299
Stock Option [Member]
Total compensation expense	8	200	11	300
Stock Option [Member] | Employee [Member]
Total compensation expense	8	19	11	21
Restricted Stock [Member] | Employee [Member]
Total compensation expense		23		255
Restricted Stock [Member] | Non-Employee [Member]
Total compensation expense		$ 125		$ 23