Goodwill (Factors Used to Measure Goodwill in Income Approach) (Detail) (Wealth Management Reporting Unit [Member], Annual [Member])	12 Months Ended
	May 31, 2014	May 31, 2013
Wealth Management Reporting Unit [Member] | Annual [Member]
Goodwill [Line Items]
Discount rate	19.50%	18.40%
Weighted-average increase in revenues	4.20%	5.00%
Weighted-average increase in expenses	4.70%	3.30%