Risk Management and Derivatives - FV of Derivative Instruments Included within Consolidated Balance Sheet (Detail) (USD $) In Millions, unless otherwise specified	Feb. 28, 2015	May 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 1,507	$ 133
Derivative Liabilities	195	85
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	1,263	108
Derivative Liabilities	169	58
Designated as Hedging Instrument | Foreign exchange forwards and options | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	762	76
Designated as Hedging Instrument | Foreign exchange forwards and options | Deferred income taxes and other long-term assets
Derivatives, Fair Value [Line Items]
Derivative Assets	454	26
Designated as Hedging Instrument | Foreign exchange forwards and options | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	141	57
Designated as Hedging Instrument | Foreign exchange forwards and options | Deferred income taxes and other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	28	1
Designated as Hedging Instrument | Interest rate swap | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	47	0
Designated as Hedging Instrument | Interest rate swap | Deferred income taxes and other long-term assets
Derivatives, Fair Value [Line Items]
Derivative Assets	0	6
Designated as Hedging Instrument | Interest rate swap | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	0	0
Designated as Hedging Instrument | Interest rate swap | Deferred income taxes and other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	0	0
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	244	25
Derivative Liabilities	26	27
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	243	25
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	26	27
Derivatives not designated as hedging instruments | Embedded derivatives | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	1	0
Derivatives not designated as hedging instruments | Embedded derivatives | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ 0	$ 0