XML 54 R39.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | May 03, 2007
Increase in net cash from by operating activities |  | $ 2,356 | $ 1,065 | $ 635 |
SIP expense - Year of grant |  |  |  |  | 50.00%
SIP expense - Remaining vesting period |  |  |  |  | 50.00%
SIP expense - Employees over 59 in year of grant |  |  |  |  | 100.00%
Percent of shares cancelled post employment |  |  |  |  | 50.00%
Over 59 percent of shares eligible |  |  |  |  | 100.00%
U.S. Treasury Securities |  | 4,200 | 4,500 |  |
Securities Purchased Under Agreement to Resell Segregated for Regulatory Purposes |  | 11,400 | 9,200 |  |
Equity method investments |  | $ 23 | 23 |  |
Property and equipment useful lives, description |  | Computer equipment is depreciated over three to five years and office furniture and equipment are depreciated over five to seven years. Intangible assets with a finite life are amortized on a straight line basis over their estimated useful lives of three years, and tested for recoverability whenever events indicate that the carrying amounts may not be recoverable. Qualifying costs for internally developed software are capitalized and amortized over the expected useful life of the developed software, not to exceed three years. |  |  |
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, before Income Tax |  |  | 11 |  |
Restructuring and Related Cost, Expected Cost |  |  | 25 |  |
Supplemental unemployment benefits severance benefits |  |  | 3 |  |
Restructuring settlement and impairment provisions |  |  | $ 22 |  |
AOCI gain reclassified to earnings | $ 32 |  |  |  |
Accumulated tax effect | $ 1 |  |  |  |
U.S. Statutory Tax Rate |  | 21.00% | 35.00% | 35.00% |
Equity Securities [Member] |  |  |  |  |
Investments at cost |  | $ 25 | $ 5 |  |
Exchange Cleared [Member] | Equity Securities [Member] |  |  |  |  |
Investments at cost |  | 5 | 6 |  |
Accounting Standards Update 2016-18 [Member] |  |  |  |  |
Increase in net cash from by operating activities |  |  | $ 923 | $ 91 |
Accounting Standards Update 2016-02 [Member] |  |  |  |  |
Change in Accounting Standard, Effect of Adoption, Quantification |  | $ 136 |  |  |
Maximum [Member] | Computer Equipment [Member] |  |  |  |  |
Property and equipment useful lives |  | 5 years |  |  |
Maximum [Member] | Office Furniture And Equipment [Member] |  |  |  |  |
Property and equipment useful lives |  | 7 years |  |  |
Maximum [Member] | Internally Developed Software [Member] |  |  |  |  |
Intangible assets useful lives |  | 3 years |  |  |
Maximum [Member] | Finite-Lived Intangible Assets [Member] |  |  |  |  |
Intangible assets useful lives |  | 3 years |  |  |
Minimum [Member] | Computer Equipment [Member] |  |  |  |  |
Property and equipment useful lives |  | 3 years |  |  |
Minimum [Member] | Office Furniture And Equipment [Member] |  |  |  |  |
Property and equipment useful lives |  | 5 years |  |  |

X
- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock and member interests in limited liability companies and partnerships of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References No definition available. + Details
Name: | ibkr_EquityMethodInvestmentsBalances
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of unvested shares to be received by employees over the age of 59 who discontinue employment with the Company without cause and continue to meet the terms of the plans' post-employment provisions. + References No definition available. + Details
Name: | ibkr_OverFiftyNinePercentUnvestedSharesEligible
Namespace Prefix: | ibkr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of unvested shares forfeited by employees who discontinue employment with the Company without cause and continue to meet the terms of the plans' post-employment provisions. + References No definition available. + Details
Name: | ibkr_PercentSharesForfeitedPostEmployment
Namespace Prefix: | ibkr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The carrying value of funds, segregated for regulatory purposes and for the exclusive benefit of customers, outstanding loaned in the form of security resale agreements if the agreement requires the purchaser to resell the identical security purchased or a security that meets the definition of "substantially the same" in the case of a dollar roll. Also includes purchases of participations in pools of securities that are subject to a resale agreement. + References No definition available. + Details
Name: | ibkr_SegregatedSecuritiesPurchasedUnderAgreementsToResell
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percent of fair value of stock grant expensed during the first year of the grant for employees who are over fifty nine years old. + References No definition available. + Details
Name: | ibkr_StockGrantedExpenseOverFiftyNine
Namespace Prefix: | ibkr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percent of fair value of stock grant expensed over the related vesting period utilizing the “graded vesting” method permitted under ASC Topic 718. + References No definition available. + Details
Name: | ibkr_StockGrantedExpenseRemainingVestingPeriod
Namespace Prefix: | ibkr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percent of fair value of stock grant expensed in the year of the grant. + References No definition available. + Details
Name: | ibkr_StockGrantedExpenseYearOfGrant
Namespace Prefix: | ibkr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments. + References No definition available. + Details
Name: | us-gaap_CostMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
Name: | us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before tax of income (loss) from an individually significant component disposed of or held-for-sale including the portion attributable to the noncontrolling interest. Excludes discontinued operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109226691&loc=SL51724579-110230 + Details
Name: | us-gaap_IncomeLossFromIndividuallySignificantComponentDisposedOfOrHeldForSaleExcludingDiscontinuedOperationsBeforeIncomeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_NetCashProvidedByUsedInOperatingActivities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 35 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68071081&loc=d3e1205-110223 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 + Details
Name: | us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringAndRelatedCostExpectedCost1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_RestructuringSettlementAndImpairmentProvisions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Liability for amount due employees, in addition to wages and any other money that employers owe employees, when their employment ends through a layoff or other termination. For example, a company may provide involuntarily terminated employees with a lump sum payment equal to one week's salary for every year of employment. + References No definition available. + Details
Name: | us-gaap_SupplementalUnemploymentBenefitsSeveranceBenefits
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of reclassification from other comprehensive income (loss) to earnings, after tax, related to translation from the functional currency to reporting currency, as a result of the sale or complete or substantially complete liquidation of an investment in a foreign entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109240241&loc=d3e32211-110900 + Details
Name: | us-gaap_TranslationAdjustmentFunctionalToReportingCurrencyGainLossReclassifiedToEarningsNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of income tax expense (benefit) from translating foreign currency financial statements into the reporting currency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=109240241&loc=d3e32022-110900 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109240241&loc=d3e32211-110900 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 + Details
Name: | us-gaap_TranslationAdjustmentFunctionalToReportingCurrencyTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TransactionTypeAxis=us-gaap_ExchangeClearedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201618Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_ComputerEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=ibkr_OfficeFurnitureAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_SoftwareAndSoftwareDevelopmentCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FiniteLivedIntangibleAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |