v3.7.0.1
STOCK-BASED COMPENSATION - Restricted Stock Units (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Restricted Stock Units, Weighted Average Grant Date Fair Value [Abstract]    
Aggregate grant date fair value   $ 200
Payment for shares withheld for tax withholdings on vesting of restricted stock units $ (326) $ (311)
PBRSU to common stock, conversion ratio 100.00%  
Common Stock    
Restricted Stock Units, Weighted Average Grant Date Fair Value [Abstract]    
Shares repurchased for tax withholdings on vesting of RSUs 70,368 58,790
2014 Equity Incentive Plan    
Restricted Stock Units, Number of Shares [Roll Forward]    
Awards granted 804,691  
Awards canceled (847,391)  
Restricted Stock Units (RSUs)    
Restricted Stock Units, Number of Shares [Roll Forward]    
Beginning balance 4,365,670  
Awards granted 804,691  
Awards vested (481,546)  
Awards canceled (777,023)  
Ending balance 3,911,792  
Restricted Stock Units (RSUs) | 2014 Equity Incentive Plan    
Restricted Stock Units, Weighted Average Grant Date Fair Value [Abstract]    
Beginning balance (in dollars per share) $ 6.23  
Awards granted (in dollars per share) 5.00 $ 5.01
Awards vested (in dollars per share) 5.87  
Awards canceled (in dollars per share) 6.24  
Ending balance (in dollars per share) $ 6.03  
Aggregate grant date fair value $ 4,000 $ 2,100
Fair value of shares vested $ 2,200 $ 2,600
Restricted Stock Units (RSUs) | Vesting period, one year    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 1 year  
Restricted Stock Units (RSUs) | Vesting period, three years    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 3 years  
PBRSUs    
Restricted Stock Units, Number of Shares [Roll Forward]    
Awards granted 378,644