Stock-Based Compensation

9 Months Ended

Aug. 31, 2019

Share-based Payment Arrangement [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, 2019:



	Options		Weighted Average Exercise Price
Options outstanding at beginning of period	7,237,544		$	16.02
Granted	—		—
Exercised	(1,263,505	)	14.78
Cancelled	(180,000	)	33.59
Options outstanding at end of period	5,794,039		$	15.75
Options exercisable at end of period	5,506,883		$	15.72

As of August 31, 2019, the weighted average remaining contractual life of stock options outstanding and stock options exercisable was 3.8 years and 3.6 years, respectively. Total unrecognized compensation expense related to unvested stock option awards was nominal as of August 31, 2019. For each of the three-month and nine-month periods ended August 31, 2019, stock-based compensation expense associated with stock options was nominal. For the three months and nine months ended August 31, 2018, stock-based compensation expense associated with stock options totaled $.2 million and $.5 million, respectively. The aggregate intrinsic values of stock options outstanding and stock options exercisable were $80.2 million and $76.8 million, respectively, at August 31, 2019. (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 $4.5 million and $3.2 million for the three months ended August 31, 2019 and 2018, respectively, related to restricted stock and PSUs. We recognized total compensation expense of $14.4 million and $11.6 million for the nine months ended August 31, 2019 and 2018, respectively, related to restricted stock and PSUs.