Condensed Consolidated Statements of Cash Flows (USD $) In Millions	3 Months Ended
	Aug. 31, 2011	Aug. 31, 2010
Operating Activities:
Net income	$ 464	$ 380
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	509	479
Provision for uncollectible accounts	43	31
Stock-based compensation	37	34
Deferred income taxes and other noncash items	131	33
Changes in assets and liabilities:
Receivables	(41)	38
Other assets	1	(30)
Accounts payable and other liabilities	(263)	(160)
Other, net	(21)	(9)
Cash provided by operating activities	860	796
Investing Activities:
Capital expenditures	(1,110)	(1,012)
Business acquisition, net of cash acquired	(111)
Proceeds from asset dispositions and other	5	3
Cash used in investing activities	(1,216)	(1,009)
Financing Activities:
Principal payments on debt	(17)	(12)
Proceeds from stock issuances	28	8
Excess tax benefit on the exercise of stock options	4	1
Dividends paid	(41)	(38)
Cash used in financing activities	(26)	(41)
Effect of exchange rate changes on cash	13	11
Net decrease in cash and cash equivalents	(369)	(243)
Cash and cash equivalents at beginning of period	2,328	1,952
Cash and cash equivalents at end of period	$ 1,959	$ 1,709