v2.4.0.6
Estimated Assumptions of Fair Value of Series C Preferred Share of 51.com (Detail) (Five One Network Development Co.Ltd, Series C Preferred Stock)
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Five One Network Development Co.Ltd | Series C Preferred Stock
   
Fair Value Measurements [Line Items]    
Risk-free interest rates 0.72% 1.27%
Expected volatility 50.92% 38.04%
- IPO 25.00% 50.00%
- Liquidation 25.00% 25.00%
- Redemption 50.00% 25.00%