v2.4.0.6
Subsequent Event (Details) (USD $)
In Millions, unless otherwise specified
1 Months Ended
Mar. 31, 2013
SEC Reserve Matter [Member]
Apr. 30, 2013
TOM [Member]
Apr. 30, 2013
eSpeed [Member]
Apr. 30, 2013
Subsequent Event [Member]
TOM [Member]
Apr. 30, 2013
Subsequent Event [Member]
eSpeed [Member]
Subsequent Event [Line Items]          
Contingency, accrual $ 10        
Percentage of acquired ownership interest   25.00% 100.00% 25.00%  
Option to acquire additional ownership percentage       25.10%  
Business acquisition, cash paid         $ 750
Future common stock issuance, payment term         15 years
Expected annual issuance of common stock         1