ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES Narrative (Details)	12 Months Ended
	May 31, 2016
Basis of Financial Statements [Abstract]
Accounting changes	In fiscal 2016, we adopted Accounting Standards Update (ASU) 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes (ASU 2015-17) on a retrospective basis. As required by ASU 2015-17, all deferred tax assets and liabilities are classified as non-current in our consolidated balance sheets, which is a change from our historical presentation whereby certain of our deferred tax assets and liabilities were classified as current and the remainder were classified as non-current. Upon adoption of ASU 2015-17, current deferred tax assets of $663 million and current deferred tax liabilities of $85 million in our May 31, 2015 consolidated balance sheet were reclassified as non-current and certain related reclassification entries were also recorded. In addition, in fiscal 2016, we also adopted the following Accounting Standards Updates, none of which had a material impact to our reported financial position or results of operations and cash flows: ASU 2016-07, Investments - Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting; ASU 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments; ASU 2016-05, Derivatives and Hedging (Topic 815): Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships; ASU 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments; ASU 2015-15, Interest - Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements - Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting; ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory; and ASU 2015-05, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Fees Paid in a Cloud Computing Arrangement.
Concentrations of Risk [Abstract]
Customer Concentrations	No single customer accounted for 10% or more of our total revenues in fiscal 2016, 2015 or 2014.
Supplier Concentrations	We outsource the design, manufacturing, assembly and delivery of certain of our hardware products to a variety of companies, many of which are located outside the United States. Further, we have simplified our supply chain processes by reducing the number of third-party manufacturing partners and the number of locations where these third-party manufacturers build our hardware products. The inability of these third-party manufacturing partners to fulfill orders for our hardware products could adversely impact future operating results of our hardware business.
Credit Risk Concentrations	Financial instruments that are potentially subject to concentrations of credit risk consist primarily of cash and cash equivalents, marketable securities, derivatives and trade receivables. Our cash and cash equivalents are generally held with large, diverse financial institutions worldwide to reduce the amount of exposure to any single financial institution. Investment policies have been implemented that limit purchases of marketable debt securities to investment-grade securities. Our derivative contracts are transacted with various financial institutions with high credit standings. We generally do not require collateral to secure accounts receivable. The risk with respect to trade receivables is mitigated by credit evaluations we perform on our customers, the short duration of our payment terms for the significant majority of our customer contracts and by the diversification of our customer base.
Property, Plant and Equipment (Impairment Assessments) [Abstract]
Impairment of Property, Plant and Equipment	We did not recognize any significant property impairment charges in fiscal 2016, 2015 or 2014.
Research and Development and Software Development Costs [Abstract]
Research and Development and Software Development Costs	Software development costs required to be capitalized under ASC 985-20, Costs of Software to be Sold, Leased or Marketed, and under ASC 350-40, Internal-Use Software, were not material to our consolidated financial statements in fiscal 2016, 2015 and 2014.