Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Condensed Cash Flow Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$ 701	$ 590
INVESTING ACTIVITIES
Capital expenditures	(1,179)	(1,044)
Proceeds from asset dispositions and other	78	6
Cash used in investing activities	(1,101)	(1,038)
FINANCING ACTIVITIES
Proceeds from short-term borrowings	299
Principal payments on debt	(2)	(12)
Proceeds from stock issuances	25	150
Dividends paid	(173)	(134)
Purchase of treasury stock	(625)	(86)
Other, net	4	(6)
Cash used in financing activities	(472)	(88)
Effect of exchange rate changes on cash	(24)	70
Net (decrease) increase in cash and cash equivalents	(896)	(466)
Cash and cash equivalents at beginning of period	3,265	3,969
Cash and cash equivalents at end of period	2,369	3,503
Consolidation Eliminations [Member]
Condensed Cash Flow Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	(27)	7
FINANCING ACTIVITIES
Net (decrease) increase in cash and cash equivalents	(27)	7
Cash and cash equivalents at beginning of period	(15)	(47)
Cash and cash equivalents at end of period	(42)	(40)
Parent Company [Member] \| Reportable Legal Entities [Member]
Condensed Cash Flow Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	785	(878)
INVESTING ACTIVITIES
Proceeds from asset dispositions and other	(5)
Cash used in investing activities	(5)
FINANCING ACTIVITIES
Proceeds from short-term borrowings	299
Net transfers from (to) Parent	(853)	744
Proceeds from stock issuances	25	150
Dividends paid	(173)	(134)
Purchase of treasury stock	(625)	(86)
Other, net		3
Cash used in financing activities	(1,327)	677
Effect of exchange rate changes on cash		(2)
Net (decrease) increase in cash and cash equivalents	(547)	(203)
Cash and cash equivalents at beginning of period	1,485	1,884
Cash and cash equivalents at end of period	938	1,681
Guarantor Subsidiaries [Member[ \| Reportable Legal Entities [Member]
Condensed Cash Flow Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	(159)	1,717
INVESTING ACTIVITIES
Capital expenditures	(983)	(985)
Proceeds from asset dispositions and other	78	6
Cash used in investing activities	(905)	(979)
FINANCING ACTIVITIES
Net transfers from (to) Parent	763	(735)
Intercompany dividends	81
Principal payments on debt		(8)
Other, net	148
Cash used in financing activities	992	(743)
Effect of exchange rate changes on cash	(5)	23
Net (decrease) increase in cash and cash equivalents	(77)	18
Cash and cash equivalents at beginning of period	257	325
Cash and cash equivalents at end of period	180	343
Non Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Cash Flow Statements Captions [Line Items]
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	102	(256)
INVESTING ACTIVITIES
Capital expenditures	(196)	(59)
Proceeds from asset dispositions and other	5
Cash used in investing activities	(191)	(59)
FINANCING ACTIVITIES
Net transfers from (to) Parent	90	(9)
Intercompany dividends	(81)
Principal payments on debt	(2)	(4)
Other, net	(144)	(9)
Cash used in financing activities	(137)	(22)
Effect of exchange rate changes on cash	(19)	49
Net (decrease) increase in cash and cash equivalents	(245)	(288)
Cash and cash equivalents at beginning of period	1,538	1,807
Cash and cash equivalents at end of period	$ 1,293	$ 1,519

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

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