Stockholders' Equity

12 Months Ended

Dec. 31, 2018

Stockholders’ Equity

2016 Stock Repurchase Program

On June 2, 2016, our Board of Directors authorized a stock repurchase program of up to $100.0 million (the “Repurchase Program”). On May 18, 2017 and December 1, 2017, our Board of Directors authorized an additional $100.0 million, respectively, increasing the Repurchase Program to an aggregate authorization of $300.0 million. No time limit has been established for the completion of the program, and the program may be suspended, discontinued or replaced by the Board of Directors at any time without prior notice. As of December 31, 2018, we have $72.6 million available under this program to repurchase additional shares.

The following table details our stock repurchases under the Repurchase Program:



	Year Ended December 31,
	2018		2017		2016
Shares of common stock repurchased and retired	756		4,674		452
Average price per share	$	53.88	$	35.94	$	41.06
Total cost	$	40,722	$	168,001	$	18,577

2018 Repurchase Transaction

On August 13, 2018, our Board of Directors authorized the use of a portion of the proceeds from the issuance of the 2023 Convertible Notes to repurchase up to $25.0 million of common stock. On August 16, 2018, 196,050 shares of our common stock were repurchased at $76.51 per share for a total cost of $15.0 million. This is a separate repurchase transaction outside of the Repurchase Program.

2015 Stock Repurchase Program

On November 5, 2015, our Board of Directors authorized a six-month stock repurchase program of up to $50.0 million (the “2015 Repurchase Program”). During the year ended December 31, 2016, we repurchased and retired 85,100 shares of our common stock for an average per share price of $34.16, at a total cost of $2.9 million, which was paid in full in 2016. The 2015 Repurchase Program expired on May 5, 2016.