Supplemental Cash Flow Information -Supplemental Cash Flow (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2019	May 31, 2018	May 31, 2017
Supplemental Cash Flow Information [Abstract]
Interest (net of capitalized interest)	$ 617	$ 524	$ 484
Income taxes	407	760	397
Income tax refunds received	(36)	(571)	(20)
Cash tax payments, net	$ 371	$ 189	$ 377

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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- Definition

Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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-Section 50
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No definition available.

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