CHINA CONTRIBUTION PLAN AND PROFIT APPROPRIATION (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
CHINA CONTRIBUTION PLAN AND PROFIT APPROPRIATION      
Employee benefit expenses $ 48,383 $ 22,556 $ 13,268
Appropriation of after-tax profits to general reserve fund, percentage 10.00%    
Limit of general reserve fund as a percentage of registered capital, after which appropriations to general reserve fund are no longer required 50.00%    
Appropriations to statutory surplus reserve fund 2,865 729 2,875
Amount of restricted net assets $ 185,913 $ 170,284