Stock-Based Compensation

9 Months Ended

Aug. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Options. We estimate the grant-date fair value of stock options using the Black-Scholes option-pricing model. The following table summarizes stock option transactions for the nine months ended August 31, 2018:



	Options		Weighted Average Exercise Price
Options outstanding at beginning of period	9,265,240		$	17.64
Granted	—		—
Exercised	(1,049,260	)	16.62
Cancelled	(33,706	)	17.29
Options outstanding at end of period	8,182,274		$	17.78
Options exercisable at end of period	7,254,706		$	18.04

As of August 31, 2018, the weighted average remaining contractual life of stock options outstanding and stock options exercisable was 3.8 years and 3.3 years, respectively. There was $.3 million of total unrecognized compensation expense related to unvested stock option awards as of August 31, 2018 that is expected to be recognized over a weighted average period of 0.9 years. For the three months ended August 31, 2018 and 2017, stock-based compensation expense associated with stock options totaled $.2 million and $.6 million, respectively. For the nine months ended August 31, 2018 and 2017, stock-based compensation expense associated with stock options totaled $.5 million and $1.7 million, respectively. The aggregate intrinsic values of stock options outstanding and stock options exercisable were $77.3 million and $68.8 million, respectively, at August 31, 2018. (The intrinsic value of a stock option is the amount by which the market value of a share of the underlying common stock exceeds the exercise price of the stock option.)

Other Stock-Based Awards. From time to time, we grant restricted stock and PSUs to various employees as a compensation benefit. We recognized total compensation expense of $3.2 million and $2.3 million for the three months ended August 31, 2018 and 2017, respectively, related to restricted stock and PSUs. We recognized total compensation expense of $11.6 million and $8.1 million for the nine months ended August 31, 2018 and 2017, respectively, related to restricted stock and PSUs.