Schedule II Valuation and Qualifying Accounts and Reserves Schedule II (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 31, 2014		May 31, 2013		May 31, 2012
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 19.3		$ 25.9		$ 22.3
Expensed	8.2		6.8		12.3
Write-Offs and Other	10.2		13.4		8.7
Balance at End of Year	17.3		19.3		25.9
Reserve for returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	26.4		57.5		33.0
Expensed	58.0		50.2		81.8
Write-Offs and Other	57.0	[1]	81.3	[1]	57.3	[1]
Balance at End of Year	27.4		26.4		57.5
Reserves for obsolescence
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	90.3		90.8		82.2
Expensed	25.1		27.2		48.1
Write-Offs and Other	28.3		27.7		39.5
Balance at End of Year	87.1		90.3		90.8
Reserve for royalty advances
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	81.5		77.8		71.8
Expensed	6.5		4.7		6.5
Write-Offs and Other	1.0		1.0		0.5
Balance at End of Year	$ 87.0		$ 81.5		$ 77.8

[1] Represents actual returns charged to the reserve