Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	May. 31, 2015	May. 31, 2014	May. 31, 2013	May. 31, 2012
Income Tax Contingency [Line Items]
Effective tax rate, change from prior period	(180.00%)	(70.00%)
Total gross unrecognized tax benefits, excluding related interest and penalties	$ 438	$ 506	$ 447	$ 285
Total gross unrecognized tax benefits, excluding related interest and penalties, amount which would affect the Company's effective tax rate if recognized in future periods	260
Increase in liability for payment of interest and penalties	(3)	55	4
Accrued interest and penalties related to uncertain tax positions (excluding federal benefit)	164	167
Estimated decrease in total gross unrecognized tax benefits as a result of resolutions of global tax examinations and expiration of applicable statutes of limitations	63
Reinvestment of the cumulative undistributed earnings of certain foreign subsidiaries	8,300
Unrecognized deferred tax liability associated with the indefinitely reinvested undistributed earnings	$ 2,700
Tax holiday, expiration period (year)	2021
Decrease in income tax expense related to tax holiday	$ 174	$ 138	$ 108
Decrease in income tax expense related to tax holiday per diluted share, (in dollars per share)	$ 0.20	$ 0.15	$ 0.12
Valuation allowance increase (decrease) related to tax benefits of certain subsidiaries with operating losses	$ 0	$ 4	$ (22)
Available domestic and foreign loss carry-forwards	36
Income tax benefits attributable to employee stock-based compensation	224	$ 135	$ 76
Tax Year 2011 | Domestic Tax Authority
Income Tax Contingency [Line Items]
Proposed increase in tax related to the foreign tax credit matter	$ 31