Share-Based Compensation

3 Months Ended

Mar. 31, 2018

Share-Based Compensation [Abstract]

Share-Based Compensation

(10)     Share-Based Compensation

As of March 31, 2018, there were 982,458 shares of common stock available for grant under the Company’s stock incentive plans. During the first three months of 2018 and 2017, the Company issued the following share-based instruments: (1) restricted stock units of 514,000 and 665,000 with weighted-average fair values per share of $26.49 and $30.48, respectively; (2) stock options of 479,000 and 265,000 with weighted-average fair values per share of $11.82 and $13.70, respectively, and weighted-average per share exercise prices of $24.53 and $23.47, respectively. In addition, during the three months ended March 31, 2018, the Company issued 10,000 unrestricted stock units with a weighted-average fair value per share of $25.40.

The fair value of restricted stock units was based on the closing price of the Company’s common stock on the New York Stock Exchange on the date of the grant and the fair value of stock options are based on the Black-Scholes model. The fair value of certain performance-based awards were estimated taking into account the features of such awards. The fair value of stock options granted during the first three months of 2018 was determined using the Black-Scholes model based on the following weighted-average assumptions: (i) expected life of 5.2 years, (ii) expected volatility of 42.01%, (iii) risk-free rate of 2.36%, and (iv) no quarterly dividends.

For the three months ended March 31, 2018 and 2017, the Company recognized, as part of general and administrative expenses, costs for share-based payment arrangements totaling $6.1 million and $4.3 million, respectively. As of March 31, 2018, the balance of unamortized share-based compensation expense was $38.9 million, which will be recognized over a weighted-average period of 2.3 years.