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Regulatory Requirements (Summary Of Capital, Capital Requirements And Excess Capital) (Details) $ in Millions | Dec. 31, 2018 USD ($)
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Net Capital / Eligible Equity | $ 6,435
Required net capital | 625
Excess regulatory capital | 5,810
IB LLC [Member] |
Net Capital / Eligible Equity | 4,882
Required net capital | 416
Excess regulatory capital | 4,466
TH LLC [Member] |
Net Capital / Eligible Equity | 159
Excess regulatory capital | 159
IBKRFS [Member] |
Net Capital / Eligible Equity | 584
Required net capital | 93
Excess regulatory capital | 491
Other Regulated Operating Companies [Member] |
Net Capital / Eligible Equity | 810
Required net capital | 116
Excess regulatory capital | $ 694

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- Definition Eligible equity is equal to the sum of audited capital and reserves and the eligible portion of subordinated debt. Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined. + References No definition available. + Details
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- Definition The amount by which the company's Total Capital exceeds the minimum required for capital adequacy purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition Minimum amount of net capital required to be maintained by the entity to engage in securities transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher SEC -Name Rule 15c3-1 -Number 240 -Section 15c3-1 + Details
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- Details
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- Details
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- Details
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- Details
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