Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 28, 2018	Feb. 28, 2018	Feb. 28, 2017
Condensed Financial Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES		$ 1,162	$ 2,645
Investing Activities:
Capital expenditures		(3,994)	(3,790)
Business acquisitions, net of cash acquired		(44)
Proceeds from asset dispositions and other		21	123
Cash used in investing activities		(4,017)	(3,667)
Financing Activities:
Proceeds from short-term borrowings, net		797
Proceeds from debt issuances		1,481	1,190
Principal payments on debt		(31)	(49)
Proceeds from stock issuances		284	265
Dividends paid		(402)	(319)
Purchase of treasury stock	$ (288)	(558)	(358)
Other, net		6	2
Cash provided by financing activities		1,577	731
Effect of exchange rate changes on cash		98	(70)
Net decrease in cash and cash equivalents		(1,180)	(361)
Cash and cash equivalents at beginning of period		3,969	3,534
Cash and cash equivalents at end of period	2,789	2,789	3,173
Consolidation Eliminations [Member]
Condensed Financial Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES		10	(2)
Financing Activities:
Net decrease in cash and cash equivalents		10	(2)
Cash and cash equivalents at beginning of period		(47)	(43)
Cash and cash equivalents at end of period	(37)	(37)	(45)
Parent Company [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES		(3,537)	(1,497)
Investing Activities:
Proceeds from asset dispositions and other		(5)	85
Cash used in investing activities		(5)	85
Financing Activities:
Proceeds from short-term borrowings, net		797
Net transfers from (to) Parent		807	117
Payment on loan between subsidiaries		210	36
Proceeds from debt issuances		1,481	1,190
Proceeds from stock issuances		284	265
Dividends paid		(402)	(319)
Purchase of treasury stock		(558)	(358)
Other, net		2	(8)
Cash provided by financing activities		2,621	923
Effect of exchange rate changes on cash		(6)	(10)
Net decrease in cash and cash equivalents		(927)	(499)
Cash and cash equivalents at beginning of period		1,884	1,974
Cash and cash equivalents at end of period	957	957	1,475
Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES		4,664	3,615
Investing Activities:
Capital expenditures		(3,746)	(3,456)
Business acquisitions, net of cash acquired		(44)
Proceeds from asset dispositions and other		23	16
Cash used in investing activities		(3,767)	(3,440)
Financing Activities:
Net transfers from (to) Parent		(895)	(148)
Payment on loan between subsidiaries			(15)
Intercompany dividends			1
Principal payments on debt		(17)	(33)
Other, net		4	(12)
Cash provided by financing activities		(908)	(207)
Effect of exchange rate changes on cash		61	7
Net decrease in cash and cash equivalents		50	(25)
Cash and cash equivalents at beginning of period		325	326
Cash and cash equivalents at end of period	375	375	301
Non Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES		25	529
Investing Activities:
Capital expenditures		(248)	(334)
Proceeds from asset dispositions and other		3	22
Cash used in investing activities		(245)	(312)
Financing Activities:
Net transfers from (to) Parent		88	31
Payment on loan between subsidiaries		(210)	(21)
Intercompany dividends			(1)
Principal payments on debt		(14)	(16)
Other, net			22
Cash provided by financing activities		(136)	15
Effect of exchange rate changes on cash		43	(67)
Net decrease in cash and cash equivalents		(313)	165
Cash and cash equivalents at beginning of period		1,807	1,277
Cash and cash equivalents at end of period	$ 1,494	$ 1,494	$ 1,442

The net cash inflow (outflow) from parent as a source of financing.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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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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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The cash outflow to reacquire common stock during the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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The cash outflow associated with security instruments that either represent a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes repayments of (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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