BASIS OF PRESENTATION, RECENT ACCOUNTING PRONOUNCEMENTS AND OTHER Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Nov. 30, 2020 |
Nov. 30, 2019 |
Nov. 30, 2020 |
Nov. 30, 2019 |
|
| Contract with Customer, Asset and Liability [Abstract] | ||||
| Revenues recognized included in opening deferred revenues balances | $ 5,900 | $ 6,200 | ||
| Revenue, Performance Obligation [Abstract] | ||||
| Remaining Performance Obligation, Amount, Total | $ 34,400 | $ 34,400 | ||
| Remaining Performance Obligation, Percentage, to be recognized in the next twelve months | 60.00% | 60.00% | ||
| Sales of Financing Receivables [Abstract] | ||||
| Sales of financing receivables | $ 300 | $ 196 | $ 977 | $ 876 |