Income Taxes - Reconciliation of Changes in Gross Balance of Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions		12 Months Ended
		May. 31, 2015	May. 31, 2014	May. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, as of the beginning of the period		$ 506	$ 447	$ 285
Gross increases related to prior period tax positions	[1]	32	814	77
Gross decreases related to prior period tax positions	[1]	(123)	(166)	(3)
Gross increases related to current period tax positions		82	125	130
Gross decreases related to current period tax positions		(9)	(30)	(9)
Settlements	[1]	(27)	(676)	0
Lapse of statute of limitations		(10)	(4)	(21)
Changes due to currency translation		(13)	(4)	(12)
UNRECOGNIZED TAX BENEFITS, AS OF THE END OF THE PERIOD		$ 438	$ 506	$ 447

[1] During the fourth quarter of the fiscal year ended May 31, 2014, the Company reached a resolution with the IRS on a U.S. Unilateral Advanced Pricing Agreement that covers intercompany transfer pricing for fiscal years 2011 through 2020. As a result, the Company recorded a gross increase in unrecognized tax benefits related to prior period tax positions, a gross decrease in unrecognized tax benefits related to prior period tax positions and a settlement. The net impact of these items resulted in a decrease to unrecognized tax benefits.