Stock Repurchase Program

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Stock Repurchase Program

Stock Repurchase Program

In September 2017, the board of directors approved $125.0 million for our share repurchase program in addition to the $150.0 million previously authorized in November 2015. At that time, $28.8 million remained available for repurchase under the 2015 authorization. The 2017 authorization thereby increased the remaining repurchase authorization to $153.8 million. This authorization commenced on the date of approval and expired December 31, 2018. Under this publicly announced plan, we repurchased 3,726,042 and 2,363,988 shares for an aggregate purchase price of $109.4 and $91.4 million during the years ended December 31, 2018 and 2017, respectively. As of December 31, 2018, we have completed the $275 million authorized stock repurchase program.

Our employees have the option to surrender shares of common stock to satisfy their tax withholding obligations that arise on the vesting of RSUs and the exercise of stock options. During the years ended December 31, 2018 and 2017, our employees surrendered 131,008 and 249,363 shares for an aggregate purchase price of $4.1 and $10.5 million, respectively.