Accounting for Stock-Based Compensation (Tables)

6 Months Ended

Nov. 30, 2011

Accounting for Stock-Based Compensation

Assumptions used in the Black-Scholes option pricing model to estimate the fair value of each stock option grant

	Six Months Ended
	November 30,
	2011		2010
Risk-free interest rate	1.5	%	1.8	%
Expected volatility of common stock	45.8	%	47.0	%
Dividend yield	1.0	%	0.0	%
Expected option term in years	5.7		5.8

Summary of stock option activity

					Weighted
			Weighted		Average
	Number of		Average		Remaining	Aggregate
	Options		Exercise		Contractual	Intrinsic
	(in thousands)		Price		Life (years)	Value
Outstanding at May 31, 2011	1,994		$	18.56
Granted	162		$	28.96
Exercised	(332	)	$	20.03
Cancelled	(45	)	$	17.81
Outstanding at November 30, 2011	1,779		$	19.65	6.5	$	3,408
Exercisable at November 30, 2011	871		$	18.27	4.2	$	2,301

Schedule of restricted share activity

	Number of		Weighted Average
	Shares		Fair Value
	(in thousands)		on Grant Date
Unvested at May 31, 2011	1,374		$	23.06
Granted	672		$	24.61
Vested	(324	)	$	26.71
Forfeited	(84	)	$	24.01
Unvested at November 30, 2011	1,638		$	22.91