Risk Management and Derivatives - FV of Derivative Instruments Included within Consolidated Balance Sheet (Detail) - USD ($) $ in Millions	Feb. 28, 2018	May 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 96	$ 241
Derivative Liabilities	656	254
Derivatives formally designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	60	126
Derivative Liabilities	515	132
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	42	113
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	18	13
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	403	59
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	112	73
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	36	115
Derivative Liabilities	141	122
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	23	103
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	0	2
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	133	107
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	0	7
Derivatives not designated as hedging instruments | Embedded derivatives | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	2	1
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	11	9
Derivatives not designated as hedging instruments | Embedded derivatives | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	3	2
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ 5	$ 6