Share-Based Awards and Options (Tables)

6 Months Ended

Nov. 30, 2011

Share - Based Awards and Options

Schedule of Compensation Cost for Share-based Payment Arrangements [Table Text Block]

The following table summarizes the share-based compensation cost charged to income for (i) all stock options granted, (ii) our restricted stock program (including PRSUs and TSRs), and (iii) our employee stock purchase plan . The total income tax benefit recognized for share-based compensation in the accompanying unaudited statements of income is also presented.

	Three Months Ended				Six Months Ended
	November 30, 2011		November 30, 2010		November 30, 2011		November 30, 2010
	(in millions)
Share-based compensation cost	$	4.4	$	4.2	$	8.4	$	7.7
Income tax benefit	$	1.5	$	1.5	$	2.8	$	2.7

Schedule of Stock Option Plan Activity [Table Text Block]

The following is a summary of our stock option plans as of and for the six months ended November 30, 2011:

	Options (in thousands)		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (in millions)
Outstanding at May 31, 2011	2,453		$	32	5.1	$	45.9
Granted	—		$	—
Forfeited	(40	)	$	40
Exercised	(49	)	$	27
Outstanding at November 30, 2011	2,364		$	33	4.6	$	23.9
Options vested and exercisable at November 30, 2011	1,979		$	32	3.9	$	23.1

Schedule of Stock Options Valuation Assumptions [Table Text Block]

The fair value of each option granted was estimated on the date of grant using the Black-Scholes valuation model with the following weighted average assumptions for grants during the period:

	Six Months Ended November 30,
	2011	2010
2005 Plan
Risk-free interest rates	—	1.74	%
Expected volatility	—	31.96	%
Dividend yields	—	0.21	%
Expected lives	—	5 years
Directors Plan
Risk-free interest rates	—	1.31	%
Expected volatility	—	31.96	%
Dividend yields	—	0.21	%
Expected lives	—	5 years

Schedule of Changes in Non-Vested Restricted Stock Awards Activity [Table Text Block]

The following table summarizes the changes in non-vested restricted stock awards for the six months ended November 30, 2011.

	Share Awards		Weighted Average Grant-Date Fair Value
	(in thousands)
Non-vested at May 31, 2011	869		$	40
Granted	467		48
Vested	(316	)	40
Forfeited	(46	)	42
Non-vested at November 30, 2011	974		44