Earnings Per Share - Reconciliation from Basic Earnings Per Share to Diluted Earnings Per Share (Detail) - $ / shares shares in Millions	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Determination of shares:
Weighted average common shares outstanding	1,623.8	1,657.8	1,697.9
Assumed conversion of dilutive stock options and awards	35.3	34.2	44.6
DILUTED WEIGHTED AVERAGE COMMON SHARES OUTSTANDING	1,659.1	1,692.0	1,742.5
Earnings per common share:
Basic (in dollars per share)	$ 1.19	$ 2.56	$ 2.21
Diluted (in dollars per share)	$ 1.17	$ 2.51	$ 2.16

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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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