Identified Intangible Assets and Goodwill - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Feb. 28, 2013	Feb. 29, 2012	May 31, 2012
Goodwill and Intangible Assets Disclosure [Line Items]
Amortization expense, which is included in selling and administrative expense	$ 3	$ 4	$ 10	$ 11
Estimated amortization expense for intangible assets subject to amortization, remainder of 2013	4		4
Estimated amortization expense for intangible assets subject to amortization, 2014	12		12
Estimated amortization expense for intangible assets subject to amortization, 2015	9		9
Estimated amortization expense for intangible assets subject to amortization, 2016	8		8
Estimated amortization expense for intangible assets subject to amortization, 2017	7		7
Goodwill	$ 131		$ 131		$ 131