v2.4.0.8

Employee Incentive Plans (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified | 0 Months Ended | 6 Months Ended | 86 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
May 03, 2007 | Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Apr. 24, 2014 | Dec. 31, 2013 | May 03, 2007 | Dec. 31, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
ROI Dollar Unit Payable |  | $ 3.1 |  |  | $ 3.1 |  | $ 5.6 |  |
Vested balance of ROI payable |  | 3.1 |  |  | 3.1 |  | 5.6 |  |
ROI dollar compensation expense |  | 0.3 |  | 0.2 |  |  |  |  |
Common Stock Shares issued under ROI Unit Stock Plan |  |  |  |  |  |  |  | 1,271,009 |
ROI Shares issued to IBG LLC |  |  |  |  |  |  |  | 1,250,000 |
2007 SIP shares issued under ROI Unit Stock Plan |  |  |  |  |  |  |  | 21,009 |
Fair value ROI Treasury Stock |  |  |  |  |  |  |  | 38.1 |
Fair Value ROI Accrual |  |  |  |  |  |  |  |  | 17.8
Maximum shares of stock distributable under 2007 Stock Incentive Plan |  | 20,000,000 |  |  | 20,000,000 | 30,000,000 | 20,000,000 |  |
Increase in 2007 Stock Incentive Plan shares |  |  |  |  |  | 10,000,000 |  |  |
Shares granted to external directors |  |  |  |  | 20,423 |  |  |  |
2007 Stock Incentive Plan Compensation Expense |  | 21.6 |  | 24.1 |  |  |  |  |
Estimated Future 2007 Stock Incentive Plan Compensation Expense |  | $ 32.5 |  |  | $ 32.5 |  |  |  |
Percent Shares Forfeited Post Employment |  |  |  |  |  |  |  | 50.00% |
Over Fifty Nine Percent Unvested Shares Eligible |  |  |  |  |  |  |  | 100.00% |
Former employees vesting schedule (Years) | 5 years |  |  |  |  |  |  |  |
Post employment vesting percentage (Years 1 - 4) |  |  |  |  |  |  |  | 12.50% |
Post employment vesting percentage (Year 5) |  |  |  |  |  |  |  | 50.00% |
Post employment shares distribution |  |  |  |  | 173,457 |  |  |  |
Incentive Plan Shares Distributed From Treasury [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares Distributed |  |  |  |  | 16,238 |  |  |  |
2007 ROI Unit Stock Plan [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Vesting Percentage |  | • 10% on the date of the IPO (or on the first anniversary of the IPO, in the case of U.S. ROI Unit holders who made the above-referenced elections after December 31, 2006); and• an additional 15% on each of the first six anniversaries of the date of the IPO, assuming continued employment with IBG, Inc. and compliance with other applicable covenants. |  |  |  |  |  |  |
2007 Stock Incentive Plan (Shares) |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Vesting Percentage |  | • 10% on the first vesting date, which approximates the anniversary of the IPO; and• an additional 15% on each of the following six anniversaries of the first vesting, assuming continued employment with IBG, Inc. and compliance with non-competition and other applicable covenants. |  |  |  |  |  |  |
Shares Distributed |  | (2,434,794) | [1] |  |  |  |  |  |
[1] | Shares cumulatively distributed under the 2007 Stock Incentive Plan include 16,238 shares from Treasury representing shares acquired at the IPO to satisfy obligations under the 2007 ROI Unit Stock Plan.

X
- Definition Percentage vested of remaining shares to former employees following discontinuation of employment during the fifth year of the post of post-employment period. + References No definition available. + Details
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- Definition Percentage vested of remaining shares to former employees following discontinuation of employment during the first four years post of the post-employment period. + References No definition available. + Details
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- 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
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- 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
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- Definition Compensation expense during the period for the ROI Dollar Unit plan. + References No definition available. + Details
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- Definition Liability related to the Company's ROI equity compensation plan. + References No definition available. + Details
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- Definition Fair Value of treasury stock issued to IBG LLC, held as treasury stock, in connection with the ROI Dollar Unit Stock Plan. + References No definition available. + Details
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- Definition Fair Value of accumulated ROI Dollar Unit value elected to be invested by employees. + References No definition available. + Details
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- Definition The maximum number of shares authorized to be granted and issued under the 2007 Stock Incentive Plan + References No definition available. + Details
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- Definition Increase in the maximum number of shares authorized to be granted and issued under the 2007 Stock Incentive Plan + References No definition available. + Details
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- Definition Compensation expense during the period for the 2007 Stock Incentive Plan. + References No definition available. + Details
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- Definition As of the balance sheet date, the aggregate estimated unrecognized future compensation costs for unvested 2007 Stock Incentive Plan shares. + References No definition available. + Details
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- Definition Number of common shares held in treasury on the financial statement date and issued under the ROI Unit Stock Plan. + References No definition available. + Details
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- Definition Number of common shares issued to IBG LLC and held as treasury stock in connection with the investment of accumulated ROI Dollar Unit earnings at the election of employees. Amount includes 21,009 shares allocated from the 2007 Stock Incentive Plan. + References No definition available. + Details
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- Definition Shares allocated from the 2007 Stock Incentive Plan to cover shares issued under the ROI Unit Stock Plan and held as treasury stock. + References No definition available. + Details
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- Definition Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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