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Regulatory Requirements (Tables) | 12 Months Ended
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Dec. 31, 2018
Regulatory Requirements [Abstract] |
Summary Of Capital, Capital Requirements And Excess Capital |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | Net Capital/ |  |  |  |  |  |
﻿ |  | Eligible Equity |  | Requirement |  | Excess
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | (in millions)
﻿IB LLC |  | $ | 4,882 |  | $ | 416 |  | $ | 4,466
﻿TH LLC |  |  | 159 |  |  | - |  |  | 159
﻿IBKRFS |  |  | 584 |  |  | 93 |  |  | 491
﻿Other regulated Operating Companies |  |  | 810 |  |  | 116 |  |  | 694
﻿ |  | $ | 6,435 |  | $ | 625 |  | $ | 5,810
﻿

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