Risk Management and Derivatives - FV of Derivative Instruments Included within Consolidated Balance Sheet (Detail) - USD ($) $ in Millions	Feb. 28, 2019	May 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 488	$ 400
Derivative Liabilities	89	190
Derivatives formally designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	410	270
Derivative Liabilities	58	156
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	343	118
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	67	152
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	58	156
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	0	0
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	78	130
Derivative Liabilities	31	34
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	71	119
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	0
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	25	26
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	0
Derivatives not designated as hedging instruments | Embedded derivatives | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	1	3
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	6	8
Derivatives not designated as hedging instruments | Embedded derivatives | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	4	2
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ 2	$ 6