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Equity And Earnings Per Share (Tables) | 9 Months Ended
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Sep. 30, 2021
Equity And Earnings Per Share [Abstract] |
IBG LLC Ownership of Member Interests |
|  | IBG, Inc. |  | Holdings |  | Total
Ownership % |  | 23.5% |  | 76.5% |  | 100.0%
Membership interests |  | 98,175,951 |  | 319,880,492 |  | 418,056,443
Earnings Per Share Basic And Diluted | Basic earnings per share is calculated utilizing net income available for common stockholders divided by the weighted average number of shares of Class A and Class B common stock outstanding for that period.
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2021 |  | 2020 |  | 2021 |  | 2020
|  | (in millions, except share or per share amounts)
Basic earnings per share |  |  |  |  |  |  |  |  |  |  |  |
Net income available for common stockholders |  | $ | 42 |  | $ | 46 |  | $ | 241 |  | $ | 124
Weighted average shares of common stock outstanding |  |  |  |  |  |  |  |  |  |  |  |
Class A |  |  | 96,229,858 |  |  | 78,509,525 |  |  | 92,814,667 |  |  | 77,542,908
Class B |  |  | 100 |  |  | 100 |  |  | 100 |  |  | 100
|  |  | 96,229,958 |  |  | 78,509,625 |  |  | 92,814,767 |  |  | 77,543,008
Basic earnings per share |  | $ | 0.44 |  | $ | 0.59 |  | $ | 2.60 |  | $ | 1.60
‎ Diluted earnings per share are calculated utilizing the Company’s basic net income available for common stockholders divided by diluted weighted average shares outstanding with no adjustments to net income available to common stockholders for potentially dilutive common shares.
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2021 |  | 2020 |  | 2021 |  | 2020
|  | (in millions, except share or per share amounts)
Diluted earnings per share |  |  |  |  |  |  |  |  |  |  |  |
Net income available for common stockholders |  | $ | 42 |  | $ | 46 |  | $ | 241 |  | $ | 124
Weighted average shares of common stock outstanding |  |  |  |  |  |  |  |  |  |  |  |
Class A |  |  |  |  |  |  |  |  |  |  |  |
Issued and outstanding |  |  | 96,229,858 |  |  | 78,509,525 |  |  | 92,814,667 |  |  | 77,542,908
Potentially dilutive common shares |  |  |  |  |  |  |  |  |  |  |  |
Issuable pursuant to employee stock incentive plans |  |  | 760,010 |  |  | 610,923 |  |  | 856,922 |  |  | 700,691
Class B |  |  | 100 |  |  | 100 |  |  | 100 |  |  | 100
|  |  | 96,989,968 |  |  | 79,120,548 |  |  | 93,671,689 |  |  | 78,243,699
Diluted earnings per share |  | $ | 0.43 |  | $ | 0.58 |  | $ | 2.58 |  | $ | 1.58

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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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