Annual report pursuant to Section 13 and 15(d)

STOCK-BASED COMPENSATION AND EMPLOYEE BENEFIT PLAN (Details)

v3.8.0.1
STOCK-BASED COMPENSATION AND EMPLOYEE BENEFIT PLAN (Details) - $ / shares
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Risk-free interest rate   1.64%
Risk-free interest rate - minimum 1.84%  
Risk-free interest rate - maximum 1.89%  
Expected volatility   37.07%
Expected volatility - minimum 36.87%  
Expected volatility - maximum 39.17%  
Dividend rate 0.00% 0.00%
Weighted-average estimated fair value per award (in dollars per share) $ 0.17 $ 0.20
Lower Range [Member]    
Expected life (in years) 4 years 6 months 3 years 3 months
Upper Range [Member]    
Expected life (in years) 5 years 6 months 4 years