Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 31, 2019	May 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
NET INCOME	$ 1,286	$ 540	$ 4,572
OTHER COMPREHENSIVE LOSS:
Foreign currency translation adjustments, net of tax benefit of $18 in 2020, $29 in 2019, and tax expense of $16 in 2018	(254)	(195)	(74)
Amortization of prior service credit and other, net of tax benefits of $25 in 2020, $28 in 2019, and $37 in 2018.	(79)	(92)	(89)
Other comprehensive income (loss)	(333)	(287)	(163)
COMPREHENSIVE INCOME	$ 953	$ 253	$ 4,409

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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