Share-Based Compensation - Schedule of Share-Based Compensation (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Total share-based compensation | $ 37 | $ 27 | $ 71 | $ 59 |
| Capitalized share-based compensation | (7) | (5) | (13) | (13) |
| Total share-based compensation expense | 30 | 22 | 58 | 46 |
| Tax benefit associated with share-based compensation expense | 0 | 2 | 2 | 2 |
| Equity Awards [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Total share-based compensation | 22 | 10 | 39 | 15 |
| Liability Awards [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Total share-based compensation | $ 15 | $ 17 | $ 32 | $ 44 |
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of capitalized and expensed compensation cost from equity-based compensation arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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