Stockholders' Equity and Redeemable Convertible Preferred Stock (Details 4) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Total compensation expense	$ 167	$ 47	$ 299	$ 134
Restricted Stock [Member] | Employee [Member]
Total compensation expense				11
Restricted Stock [Member] | Non-Employee [Member]
Total compensation expense	125	33	255	33
Restricted Stock Units [Member] | Employee [Member]
Total compensation expense	23		23
Stock Option [Member] | Employee [Member]
Total compensation expense	$ 19	$ 14	$ 21	$ 90