Other Financial Data (Details) - Schedule of Other Financial Data Other Than Accumulated Other Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 31, 2013		May 31, 2012		May 31, 2011
Schedule of Other Financial Data Other Than Accumulated Other Comprehensive Income [Abstract]
Advertising expense	$ 146.4		$ 145.0		$ 151.9
Prepublication and production costs	149.0		127.3		125.1
Amortization of prepublication and production costs	48.9	[1]	55.1	[1]	51.1	[1]
Foreign currency transaction gain (loss)	(0.5)		0.7		(1.3)
Purchases related to contractual commitments for minimum print quantities during fiscal years	$ 54.8		$ 61.1		$ 44.9

[1] Includes amortization of prepublication and production costs.