ACQUISITIONS - UNAUDITED PRO FORMA FINANCIAL INFORMATION (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017
Acquisitions Proforma [Abstract]
Total revenues	$ 9,771	$ 9,241	$ 28,579	$ 27,366
Net income (loss)	$ (4,024)	$ 2,220	$ 418	$ 5,772
Basic earnings (loss) per share	$ (0.98)	$ 0.54	$ 0.10	$ 1.40
Diluted earnings (loss) per share	$ (0.98)	$ 0.53	$ 0.10	$ 1.37

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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