XML 49 R38.htm IDEA: XBRL DOCUMENT v3.25.3

Organization Of Business (Details) - employee	Sep. 30, 2025	May 03, 2007
Number of employees	3,131
IBG LLC [Member]
IBG Inc. ownership % of IBG LLC	26.30%	10.00%

X

- Definition

Number of persons employed by the Entity

+ References

No definition available.

+ Details

Name:	dei_EntityNumberOfEmployees
Namespace Prefix:	dei_
Data Type:	xbrli:decimalItemType
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

- Details

Name:	srt_OwnershipAxis=ibkr_IbgLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: