Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 31, 2019	Aug. 31, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 17,757
Translation adjustments	(83)	$ (162)
Ending Balance	18,166	19,173
Foreign Currency Translation Loss [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(954)	(759)
Translation adjustments	(83)	(162)
Ending Balance	(1,036)	(921)
Foreign Currency Translation Loss [Member] \| ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Reclassification to retained earnings due to the adoption of ASU 2018-02	1
Retirement Plans Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	89	181
Reclassifications from AOCI	(21)	(23)
Ending Balance	118	158
Retirement Plans Adjustments [Member] \| ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Reclassification to retained earnings due to the adoption of ASU 2018-02	50
Accumulated Other Comprehensive (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(865)	(578)
Ending Balance	$ (918)	$ (763)

Tax Cuts and Jobs Act of 2017, reclassification from AOCI to retained earnings.

No definition available.

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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.

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No definition available.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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