Equity Incentive Plan - Compensation Expense (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Compensation expense $ 904 $ 1,563
General and Administrative Expense [Member]    
Compensation expense 836 1,524
Selling and Marketing Expense [Member]    
Compensation expense $ 68 $ 39