Risk Management and Derivatives - FV of Derivative Instruments Included within Consolidated Balance Sheet (Detail) - USD ($) $ in Millions	Nov. 30, 2015	May. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 1,483	$ 1,639
Derivative Liabilities	211	175
Derivatives formally designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	1,274	1,423
Derivative Liabilities	81	144
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	860	825
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	414	520
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	75	140
Derivatives formally designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	1	4
Derivatives formally designated as hedging instruments | Interest rate swaps | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	0	78
Derivatives formally designated as hedging instruments | Interest rate swaps | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	5	0
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	209	216
Derivative Liabilities	130	31
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	176	209
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	26	0
Derivatives not designated as hedging instruments | Foreign exchange forwards and options | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	120	20
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	2	2
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other assets
Derivatives, Fair Value [Line Items]
Derivative Assets	5	5
Derivatives not designated as hedging instruments | Embedded derivatives | Accrued liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	2	2
Derivatives not designated as hedging instruments | Embedded derivatives | Deferred income taxes and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ 8	$ 9