Stock-Based Compensation (Tables)

12 Months Ended

May 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Non-qualified Stock Options Granted

The table below sets forth the non-qualified stock options granted during each of the last three fiscal years.  For each grant, the exercise price was equal to the closing market price of the underlying common shares at each respective grant date.  The fair values of these stock options were based on the Black-Scholes option pricing model, calculated at the respective grant dates.  The calculated pre-tax stock-based compensation expense for these stock options, which is after an estimate of forfeitures, will be recognized on a straight-line basis over the respective vesting periods of the stock options.

(in thousands, except per share amounts)	2018		2017		2016
Granted		90		111		154
Weighted average exercise price, per share	$	47.76	$	42.30	$	30.92
Weighted average grant date fair value, per share	$	14.99	$	11.60	$	9.55
Pre-tax stock-based compensation, net of forfeitures	$	1,203	$	1,146	$	1,305

Schedule of Assumptions Used to Determine Fair Value of Stock Options

The weighted average fair value of stock options granted in fiscal 2018, fiscal 2017 and fiscal 2016 was based on the following weighted average assumptions:

	2018			2017			2016
Assumptions used:
Dividend yield		1.81	%		2.59	%		2.33	%
Expected volatility		36.65	%		36.86	%		38.40	%
Risk-free interest rate		1.98	%		1.15	%		1.98	%
Expected life (years)		6.0			6.0			6.0

Summary of Stock Option Activity

The following tables summarize our stock option activity for the years ended May 31:

	2018					2017					2016
(in thousands, except per share amounts)	Stock Options			Weighted Average Exercise Price		Stock Options			Weighted Average Exercise Price		Stock Options			Weighted Average Exercise Price
Outstanding, beginning of year		2,307		$	20.99		3,306		$	19.01		4,044		$	18.25
Granted		90			47.76		111			42.30		154			30.92
Exercised		(371	)		20.37		(1,076	)		16.90		(874	)		17.22
Forfeited		(7	)		33.02		(34	)		29.95		(18	)		32.25
Outstanding, end of year		2,019			22.26		2,307			20.99		3,306			19.01
Exercisable at end of year		1,800			20.03		2,067			19.17		3,059			17.85

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range

			Weighted
			Average
			Remaining		Aggregate
	Number of		Contractual		Intrinsic
	StockOptions		Life		Value
	(in thousands)		(in years)		(in thousands)
May 31, 2018
Outstanding		2,019		3.59	$	51,858
Exercisable		1,800		3.06	$	50,673
May 31, 2017
Outstanding		2,307		3.95	$	48,509
Exercisable		2,067		3.47	$	47,488
May 31, 2016
Outstanding		3,306		4.33	$	61,178
Exercisable		3,059		4.01	$	60,082

Summary of Non-Vested Stock Option Awards

The following table summarizes information about non-vested stock option awards for the year ended May 31, 2018:

				Weighted Average
	Number of			Grant Date
	Stock Options			Fair Value
	(in thousands)			per share
Non-vested, beginning of year		240		$	9.99
Granted		90			14.99
Vested		(104	)		11.06
Forfeited		(7	)		9.59
Non-vested, end of year		219		$	11.55

Schedule of Service-Based Restricted Common Shares Granted

The table below sets forth the service-based restricted common shares we granted during each of fiscal 2018, fiscal 2017 and fiscal 2016.  The calculated pre-tax stock-based compensation expense for these restricted common shares will be recognized on a straight-line basis over their respective vesting periods.

(in thousands, except per share amounts)	2018		2017		2016
Granted		176		525		217
Weighted average grant date fair value, per share	$	47.88	$	42.28	$	29.49
Pre-tax stock-based compensation, net of forfeitures	$	7,605	$	19,841	$	5,800

Summary of Activity for Service-Based Restricted Common Shares

The following tables summarize the activity for our service-based restricted common shares for the years ended May 31:

	2018					2017					2016
(in thousands, except per share amounts)	Restricted Common Shares			Weighted Average Grant Date Fair Value		Restricted Common Shares			Weighted Average Grant Date Fair Value		Restricted Common Shares			Weighted Average Grant Date Fair Value
Outstanding, beginning of year		865		$	39.49		698		$	33.69		635		$	33.65
Granted		176			47.88		525			42.28		217			29.49
Vested		(205	)		40.96		(310	)		31.81		(120	)		24.14
Forfeited		(40	)		41.58		(48	)		38.82		(34	)		34.53
Outstanding, end of year		796			40.80		865			39.49		698			33.69
Weighted average remaining contractual life of
outstanding restricted common shares (in years)		1.21					1.57					1.04
Aggregate intrinsic value of outstanding restricted
common shares	$	38,160				$	36,298				$	26,059
Aggregate intrinsic value of restricted common shares
vested during the year	$	10,330				$	12,840				$	3,527

Schedule of Assumptions Used to Determine Grant Date Fair Value of Market Based Restricted Common Shares

The following assumptions were used to determine the grant-date fair value and the derived service period for these market-based restricted common shares:

Dividend yield	1.60	%
Expected volatility	44.00	%
Risk-free interest rate	1.70	%

Performance Shares Granted

The table below sets forth the performance shares we granted (at target levels) during fiscal 2018, fiscal 2017 and fiscal 2016:

(in thousands, except per share amounts)	2018		2017		2016
Granted		54		67		87
Weighted average grant date fair value, per share	$	50.61	$	44.91	$	31.12
Pre-tax stock-based compensation	$	2,748	$	2,995	$	2,623