Segment Information (Details 2) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Major customers      
Revenues from major customer $ 904,498,793 $ 731,078,833 $ 462,439,368
Accounts receivable from major customer 415,150,008 357,442,102  
Customer A | Real Estate Online Services      
Major customers      
Revenues from major customer     6,871,686
Customer A | Real Estate Brokerage Services      
Major customers      
Revenues from major customer     42,483,101
Customer A | Real Estate Information and Consulting Services      
Major customers      
Revenues from major customer     6,356,080
Customer A | Other Services      
Major customers      
Revenues from major customer     213,754
Revenues | Customer accounting risk | Customer A      
Major customers      
Revenues from major customer     55,924,621
Accounts receivable | Credit risk | Customer A      
Major customers      
Accounts receivable from major customer 53,534,294 43,318,976  
Customer deposits | Customer deposits | Customer B      
Major customers      
Customer deposits from major customer 33,540,800 56,000,000  
Customer deposits | Customer deposits | Customer C      
Major customers      
Customer deposits from major customer 24,513,750    
Customer deposits | Customer deposits | Customer D      
Major customers      
Customer deposits from major customer 23,206,350    
Customer deposits | Customer deposits | Customer E      
Major customers      
Customer deposits from major customer   $ 8,200,900