The Company and Summary of Significant Accounting Policies (Tables)
 6 Months Ended
Jun. 30, 2012
The Company and Summary of Significant Accounting Policies [Abstract]  
Schedule of concentrations equal to or exceeding 10% of the Company's accounts receivable and revenue
                 
    Accounts Receivable  
    December 31,
2011		     June 30,
2012		  

Google

     45 %      35 % 

Platform Customer A

     11       13  

 

                                 
    Revenue  
    Three months ended
June 30,		     Six months ended
June 30,		  
    2011     2012     2011     2012  

Google

     54 %      56 %      55 %      59 % 
Schedule of platform customers received revenue-share payments equal to or exceeding 10% of the Company's cost of revenue
                                 
    Cost of Revenue  
    Three months ended
June 30,		     Six months ended
June 30,		  
    2011     2012     2011     2012  

Platform Customer A

     16 %      20 %      16 %      20 % 

Platform Customer B (1)

     N/A       17       N/A       17  

Platform Customer C

     21       13       22       13  

Platform Customer D (1)

     N/A       12       N/A       12  

 

Note:

(1) For the three and six months ended June 30, 2011, the revenue share payments received by Platform Customers B and D were less than 10%.