v2.4.0.8
Documentation and Entity Information
6 Months Ended
Jun. 30, 2014
Aug. 11, 2014
Common Class A
Aug. 11, 2014
Common Class B
Entity Registrant Name Interactive Brokers Group, Inc.    
Entity Central Index Key 0001381197    
Document Type 10-Q    
Document Period End Date Jun. 30, 2014    
Amendment Flag false    
Fiscal Year Focus 2014    
Fiscal Period Focus Q2    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Common Stock Shares Outstanding   57,098,889 100