Income Taxes (Details 7) - USD ($) $ in Millions	May 31, 2016	May 31, 2015
Components Of Deferred Tax Liabilities [Abstract]
Property, equipment, leases and intangibles	$ 4,767	$ 3,872
Employee benefits	0	13
Other	343	414
Deferred Tax Liabilities	$ 5,110	$ 4,299

Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51675352&loc=d3e28680-109314

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319

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