SHARE-BASED COMPENSATION (Tables)
12 Months Ended
Dec. 31, 2014
SHARE-BASED COMPENSATION [Abstract]  
Summary of share options granted to both employees and non-employees
Weighted-
Number of average
Options exercise price
Outstanding at December 31, 2013 29,920,388       0.40  
Options granted     3,475,132       1.33  
Options exercised     (10,372,019 )     0.28  
Options expired or canceled     (950,230 )     0.52  
Options forfeited     (50,002 )     1.85  
Outstanding at December 31, 2014     22,023,269       0.59  
Vested and expected to vest at December 31, 2014     21,428,424       0.59  
Summary of restricted shares granted to both employees and non-employees
Weighted
Number of average
restricted grant date
shares fair value
Non-vested at December 31, 2013     26,000       1.00  
Vested     (26,000 )     1.00  
Non-vested at December 31, 2014     -       -  
Summary of information with respect to options outstanding
Options outstanding Options exercisable  
Weighted-                       Weighted-              
Average                       average              
Remaining     Weighted-     Intrinsic           remaining     Weighted-     Intrinsic  
Range of     Number of     Contractual     average     value as of     Number of     contractual     Average     value as of  
exercise     options     life     exercise     December     options     life     Exercise     December  
price     outstanding     (years)     price     31,2014     exercisable     (years)     Price     31,2014  
                                                   
  *0.00-0.38       16,395,343       5.14       0.17               12,457,211       4.53       0.16          
  0.40-0.63       156,000       7.47       0.48               53,600       4.65       0.47          
  0.68-0.97       1,395,556       7.37       0.85               489,556       4.39       0.81          
  1.00-1.39       351,570       3.17       1.22               341,970       3.11       1.23          
  1.47-1.60       63,100       2.30       1.57               63,100       2.30       1.57          
  1.73-2.10       2,207,200       8.92       1.93               207,200       0.47       1.96          
  2.27-2.59       623,000       1.48       2.50               623,000       1.48       2.50          
  2.75-2.82       506,500       1.20       2.81               506,500       1.20       2.81          
  3.00-3.37       185,000       1.38       3.14               185,000       1.38       3.14          
  4.22-4.55       140,000       1.29       4.46               140,000       1.29       4.46          
          22,023,269       5.39       0.59       22,969       15,067,137       4.12       0.50       17,100  

 

 

* The exercise price was $0.0001.

Employee [Member] | Five years vesting period [Member]  
Share-based compensation [Line Items]  
Schedule of assumptions for option grants
  2012       2013       2014
Risk-free interest rates (%)(1)   1.04-1.57       1.55-1.62       1.37-1.75
Expected life(2)   5.7-5.8 years       5.4-6.2 years       6.38-6.47years
Expected dividend yield (%)(3)              
Expected volatility (%)(4)     50-51       52-53       67-68
Employee [Member] | One year vesting period [Member]  
Share-based compensation [Line Items]  
Schedule of assumptions for option grants
2012     2013     2014
Risk-free interest rates (%)(1)   0.18-0.21       0.13       0.10
Expected life(2)   1 year       1 year       1year
Expected dividend yield (%)(3)              
Expected volatility (%)(4)     52-59       52-53       67-68

 

 
(1)

 The risk-free interest rate is based on the United States Treasury Bill for a term of 1, 5 or 7 years which is consistent with the expected life of the awards.

 

(2) 

The Company calculates the expected life of share options based on its employees' historical experience.

 

(3) 

The Company currently has no history or expectation of paying dividends on its ordinary shares.

 

(4) 

The Company estimated volatility based on the historical volatilities of the Company.
Non-employee [Member]  
Share-based compensation [Line Items]  
Schedule of assumptions for option grants
2012     2013     2014
Risk-free interest rates (%)(1)   0.56-1.22       0.65-1.85       0.10-1.37
Expected life(2)   5 years       1 year       1-6.47years
Expected dividend yield (%)(3)              
Expected volatility (%) (4)     50-51       45-49       67-68

 

 
(1) 

The risk-free interest rate is based on the United States Treasury Bill for a term of 5 years consistent with the expected life of the awards.

 

(2) 

The Company uses a vesting term of 5 years as the expected life of share options, except for performance based options which had an exercise price of $0.0001 and a 1 year vesting term period based on historical experience.

 

(3)

 The Company currently has no history or expectation of paying dividends on its ordinary shares.

 

(4) 

The Company estimated volatility based on the historical volatilities of the Company.