XML 55 R42.htm IDEA: XBRL DOCUMENT
v3.25.2

Equity And Earnings Per Share (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 36 Months Ended | 78 Months Ended | 168 Months Ended | 218 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 30, 2025 | Jul. 17, 2025 | Jul. 26, 2023 | Oct. 07, 2019 | Mar. 31, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Jun. 30, 2024 | Mar. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2010 | Jun. 30, 2025 | Dec. 31, 2024 | Jun. 30, 2025 | May 03, 2007
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IBG Holdings Redemption of IBG LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.00%
IBG Holdings LLC Ownership Percentage of Class B Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00%
Amortization period DTA (years) |  |  |  |  |  |  |  |  |  | 15 years |  |  |  |  |  |
Unamortized deferred tax asset arising from equity offerings |  |  |  |  |  | $ 188 |  |  |  | $ 188 |  |  | $ 188 | $ 196 | $ 188 |
Percent of tax savings owed to IBG Holdings LLC |  |  |  |  |  |  |  |  |  | 85.00% |  |  |  |  |  |
Percentage of tax savings retained by IBG Inc. |  |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |  |
Deferred tax asset from common stock offerings |  |  |  |  |  | $ 688 |  |  |  | $ 688 |  |  | $ 688 |  | 688 |
Tax savings owed to IBG Holdings LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 585 |
Tax savings retained by IBG Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 103 |
Tax savings paid to IBG Holdings LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 308 |
Shares reserved for future issuance |  |  |  |  |  | 1,440,000,000 |  |  |  | 1,440,000,000 |  |  | 1,440,000,000 |  | 1,440,000,000 | 360,000,000
Shares redeemed by IBG Holdings from IBG LLC |  |  |  |  |  |  |  |  |  |  |  | 20,053,036 |  |  |  |
Cash Redemptions IBG Holdings |  |  |  |  |  |  |  |  |  |  |  | $ 114 |  |  |  |
Fair Value of Issued Shares in Exchange for Membership Interests |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000 |  |
Stock registered, number of common stock |  |  | 2,520,000 | 4,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued |  |  |  |  |  |  |  |  |  |  |  |  |  | 161,777,780 |  |
Distribution from IBG LLC |  |  |  |  |  |  |  |  |  | $ 653 |  |  |  |  |  |
Cash distribution to IBG, Inc. |  |  |  |  |  |  |  |  |  | 169 |  |  |  |  |  |
Dividend per share |  |  |  |  | $ 0.0625 | $ 0.08 | $ 0.0625 | $ 0.0625 | $ 0.025 |  |  |  |  |  |  |
Dividends paid to common shareholders |  |  |  |  | $ 27 | $ 35 |  |  |  | $ 62 | $ 38 |  |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value of Issued Shares in Exchange for Membership Interests | $ 254 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued | 3,836,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend per share |  | $ 0.08 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | O 2025 Q3 Dividends [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Declaration Date |  | Jul. 17, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment Date |  | Sep. 12, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Record Date |  | Sep. 01, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |
IBG LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IBG Inc. ownership % of IBG LLC |  |  |  |  |  | 26.00% |  |  |  | 26.00% |  |  | 26.00% |  | 26.00% | 10.00%
IBG Holdings ownership % of IBG LLC |  |  |  |  |  | 74.00% |  |  |  | 74.00% |  |  | 74.00% |  | 74.00% | 90.00%
Shares Issued |  |  |  |  |  |  |  |  |  |  |  |  | 2,880,000 |  |  |
IBG LLC [Member] | Thomas Peterffy And Affiliates [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Majority stakeholder percentage |  |  |  |  |  | 91.40% |  |  |  | 91.40% |  |  | 91.40% |  | 91.40% | 84.60%
Common Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par value |  |  |  |  |  | $ 0.01 |  |  |  | $ 0.01 |  |  | $ 0.01 | $ 0.01 | $ 0.01 |
Common Class B [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity And Earnings Per Share [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par value |  |  |  |  |  | $ 0.01 |  |  |  | $ 0.01 |  |  | $ 0.01 | $ 0.01 | $ 0.01 |

X
- Definition Total value of shares redeemed by IBG Holdings from IBG LLC funded by using cash on hand at IBG LLC. + References No definition available. + Details
Name: | ibkr_CashRedemptions
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Useful life of deferred tax asset related to common stock offerings. This deferred tax asset is amortized as additional deferred income tax expense from the IPO date and from the additional redemption dates. + References No definition available. + Details
Name: | ibkr_DTUsefulLife
Namespace Prefix: | ibkr_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of tax savings retained by the Company according to the "Tax Receivable Agreement" + References No definition available. + Details
Name: | ibkr_DeferredTaxAssetPercentageRetainedByCompany
Namespace Prefix: | ibkr_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition 'Cumulative amount of tax savings realized by the Company, from the IPO and follow-on offerings, that has been paid to IBG Holdings, LLC according to the "Tax Receivable Agreement". + References No definition available. + Details
Name: | ibkr_DeferredTaxAssetsPaidToHoldings
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Cumulative amount of tax savings realized by the Company, from the IPO and follow-on offerings, that is payable to IBG Holdings, LLC according to the "Tax Receivable Agreement". + References No definition available. + Details
Name: | ibkr_DeferredTaxAssetsPayableToHoldings
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percent of tax savings realized by the Company that is payable to Holdings according to the "Tax Receivable Agreement" + References No definition available. + Details
Name: | ibkr_DeferredTaxAssetsPercentagePayableToHoldings
Namespace Prefix: | ibkr_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Cumulative amount of tax savings realized by the Company, from the IPO and follow-on offerings, that is retained by the Company according to the "Tax Receivable Agreement". + References No definition available. + Details
Name: | ibkr_DeferredTaxAssetsValueNotPayableToCompany
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Distributions made by IBG LLC to controlling and noncontrolling interests. + References No definition available. + Details
Name: | ibkr_DividendsPaid
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition EquityAndEarningsPerShareLineItems + References No definition available. + Details
Name: | ibkr_EquityAndEarningsPerShareLineItems
Namespace Prefix: | ibkr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair Value of Issued Shares in Exchange for Membership Interests. + References No definition available. + Details
Name: | ibkr_FairValueOfIssuedSharesInExchangeForMembershipInterests
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition IBG Holdings LLC's ownership percentage in Class B common stock. + References No definition available. + Details
Name: | ibkr_HoldingsOwnershipPercentageClassB
Namespace Prefix: | ibkr_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percent ownership of IBG LLC redeemed by IBG Holdings from its members in connection with the consummation of the IPO. + References No definition available. + Details
Name: | ibkr_HoldingsRedemptionIBGLLC
Namespace Prefix: | ibkr_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Majority Stakeholder Percentage + References No definition available. + Details
Name: | ibkr_MajorityStakeholderPercentage
Namespace Prefix: | ibkr_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of membership interests redeemed by IBG Holdings, LLC from IBG LLC which were funded using cash on hand at IBG LLC. + References No definition available. + Details
Name: | ibkr_ShareRedeemedByIBGHoldings
Namespace Prefix: | ibkr_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Registered During Period Shares, Common Stock + References No definition available. + Details
Name: | ibkr_StockRegisteredDuringPeriodSharesCommonStock
Namespace Prefix: | ibkr_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The unamortized balance of the cumulative deferred tax asset arising from Common Stock offerings. + References No definition available. + Details
Name: | ibkr_UnamortizedDeferredTaxAssetArisingFromEquityOfferings
Namespace Prefix: | ibkr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50 percent or less owned persons accounted for using the equity method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 + Details
Name: | us-gaap_CashDividendsPaidToParentCompany
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1 + Details
Name: | us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
Name: | us-gaap_DeferredTaxAssetsTaxCreditCarryforwards
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Date the declared dividend will be paid, in YYYY-MM-DD format. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-3 + Details
Name: | us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date the dividend to be paid was declared, in YYYY-MM-DD format. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-3 + Details
Name: | us-gaap_DividendsPayableDateDeclaredDayMonthAndYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format. + References No definition available. + Details
Name: | us-gaap_DividendsPayableDateOfRecordDayMonthAndYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-15 + Details
Name: | us-gaap_PaymentsOfDividendsCommonStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -SubTopic 10 -Topic 505 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481112/505-10-50-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478448/946-505-50-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(4)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(i)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479886/946-10-S99-3 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DividendsAxis=ibkr_O2025Q3DividendsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_OwnershipAxis=ibkr_IbgLlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=ibkr_ThomasPeterffyAndAffiliatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |