Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Net income (loss)	$ 402.5	$ 353.6
Subtract:
Net income (loss) attributable to noncontrolling interest	5.4	4.7
Total	$ 397.1	$ 348.9
Weighted-average shares outstanding:
Basic	289.4	288.3
Dilutive effects:
Diluted	292.9	292.4
Net income (loss) per common share:
Basic	$ 1.37	$ 1.21
Diluted	$ 1.36	$ 1.19
Nonqualified Stock Options
Dilutive effects:
Stock-based compensation awards	1.4	1.9
Restricted Stock Units
Dilutive effects:
Stock-based compensation awards	1.9	2.0
Performance Share Awards
Dilutive effects:
Stock-based compensation awards	0.2	0.2

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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