CONDENSED CONSOLIDATED BALANCE SHEETS PARENTHETICAL - USD ($) shares in Millions, $ in Millions	Aug. 31, 2018	May 31, 2018
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 348	$ 370
Preferred stock par value per share	$ 0.01	$ 0.01
Preferred stock shares authorized	1.0	1.0
Preferred stock shares outstanding	0.0	0.0
Common stock par value per share	$ 0.01	$ 0.01
Common stock shares authorized	11,000.0	11,000.0
Common stock shares outstanding	3,811.0	3,997.0

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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