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Employee Incentive Plans (Share Grants And Fair Value) (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended | 116 Months Ended | 152 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2019
Employee Incentive Plans [Abstract] |  |  |  |  |  |  |
Shares granted |  | 1,374,217 | [1] | 1,146,267 | 946,489 | 23,551,137 |
Fair Value - Date of Grant |  | $ 65 |  | $ 62 | $ 57 | $ 504 | $ 65
Shares Granted IPO to Date |  |  |  |  |  |  | 27,018,110
Fair Value - Date of Grant IPO to Date |  |  |  |  |  |  | $ 688
Stock Incentive Plan Granted Shares Adjustment | 343 |  |  |  |  |  |
[1] | Stock Incentive Plan number of granted restricted stock units related to 2019 was adjusted by 343 additional restricted stock units during the nine months ended September 30, 2020.

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- Definition Fair Value of shares granted under the 2007 Stock Incentive Plan. + References No definition available. + Details
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- Definition Fair Value of all shares granted under the 2007 Stock Incentive Plan from the IPO to date. + References No definition available. + Details
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- Definition Number of shares granted under the 2007 Stock Incentive Plan. + References No definition available. + Details
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