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Equity (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2015
Equity [Abstract] |
Summary of common stock |
| As of December 31, 2015 |  | As of December 31, 2014
(In millions) | Authorized |  | Issued |  | Outstanding |  | Authorized |  | Issued |  | Outstanding
Common stock | 1,000.0 |  |  | 241.2 |  |  | 218.6 |  |  | 1,000.0 |  |  | 257.1 |  |  | 234.6 |

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- Definition Summary of common stock. + References No definition available. + Details
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- References No definition available. + Details
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