v2.4.0.8

Segment And Geographic Information (Segment Table) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013 | Dec. 31, 2013
Segment Reporting Information [Line Items] |  |  |  |  |
Net revenues | $ 309,299 | $ 283,956 | $ 664,207 | $ 500,030 |
Income before income taxes | 174,209 | 133,926 | 392,353 | 216,149 |
Assets | 40,155,499 |  | 40,155,499 |  | 37,870,700
Electronic Brokerage [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net revenues | 220,600 | 212,500 | 444,300 | 407,800 |
Income before income taxes | 131,400 | 123,300 | 265,700 | 234,300 |
Assets | 34,560,600 |  | 34,560,600 |  | 31,333,500
Market Making [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net revenues | 91,900 | 67,400 | 225,000 | 91,000 |
Income before income taxes | 46,500 | 7,600 | 134,600 | (21,400) |
Assets | 12,190,700 |  | 12,190,700 |  | 12,139,500
Corporate And Eliminations [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net revenues | (3,200) | 4,000 | (5,100) | 1,200 |
Income before income taxes | (3,700) | 3,000 | (8,000) | 3,200 |
Assets | $ (6,595,800) |  | $ (6,595,800) |  | $ (5,602,300)

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