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Organization Of Business (Details) - employee	Sep. 30, 2021	May 03, 2007
Number of employees	2,471
IBG LLC [Member]
IBG Inc. ownership % of IBG LLC	23.50%	10.00%

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- Definition

Number of persons employed by the Entity

+ References

No definition available.

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Namespace Prefix:	dei_
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X

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: