Common Stock	6 Months Ended
Jun. 30, 2015
Stockholders' Equity Note [Abstract]
Common Stock	Common Stock As of June 30, 2015 and December 31, 2014, 62,784,449 and 62,981,229 shares of our common stock were outstanding, respectively. During the three months ended June 30, 2015 and 2014, 102,562 and 112,108 shares of common stock, respectively, were issued primarily upon: (a) the satisfaction of required conditions under certain of our share-based compensation plans, (b) the purchase of common stock pursuant to our employee stock purchase plan and (c) the exercise of stock options. During the six months ended June 30, 2015 and 2014, 281,490 and 562,724 shares of common stock, respectively, were issued primarily upon: (a) the satisfaction of required conditions under certain of our share-based compensation plans, (b) the exercise of stock options and (c) the purchase of common stock pursuant to our employee stock purchase plan. On September 26, 2011, our Board of Directors authorized us to repurchase up to $100.0 million of our outstanding common stock. On December 5, 2013 and October 23, 2014, our Board of Directors authorized us to repurchase up to an additional $100.0 million and $250.0 million of our outstanding common stock, respectively. During 2015, we repurchased approximately 0.5 million shares of our common stock for approximately $21.1 million. Since the inception of the repurchase programs through June 30, 2015, we have repurchased 8.0 million shares of our common stock for approximately $304.7 million. As of June 30, 2015, there remained authorization for us to repurchase approximately $145.3 million of our shares. The current repurchase program does not obligate the Company to acquire any particular amount of common stock and may be suspended, recommenced or discontinued at any time or from time to time without prior notice. Repurchases may be made from time to time to the extent permitted by securities laws and other legal requirements, including provisions in our credit agreement placing limitations on such repurchases. The repurchase programs have been and will be funded from our operations.

Common Stock

6 Months Ended

Jun. 30, 2015

Stockholders' Equity Note [Abstract]

As of June 30, 2015 and December 31, 2014, 62,784,449 and 62,981,229 shares of our common stock were outstanding, respectively.

During the three months ended June 30, 2015 and 2014, 102,562 and 112,108 shares of common stock, respectively, were issued primarily upon: (a) the satisfaction of required conditions under certain of our share-based compensation plans, (b) the purchase of common stock pursuant to our employee stock purchase plan and (c) the exercise of stock options. During the six months ended June 30, 2015 and 2014, 281,490 and 562,724 shares of common stock, respectively, were issued primarily upon: (a) the satisfaction of required conditions under certain of our share-based compensation plans, (b) the exercise of stock options and (c) the purchase of common stock pursuant to our employee stock purchase plan.

On September 26, 2011, our Board of Directors authorized us to repurchase up to $100.0 million of our outstanding common stock. On December 5, 2013 and October 23, 2014, our Board of Directors authorized us to repurchase up to an additional $100.0 million and $250.0 million of our outstanding common stock, respectively. During 2015, we repurchased approximately 0.5 million shares of our common stock for approximately $21.1 million. Since the inception of the repurchase programs through June 30, 2015, we have repurchased 8.0 million shares of our common stock for approximately $304.7 million. As of June 30, 2015, there remained authorization for us to repurchase approximately $145.3 million of our shares. The current repurchase program does not obligate the Company to acquire any particular amount of common stock and may be suspended, recommenced or discontinued at any time or from time to time without prior notice. Repurchases may be made from time to time to the extent permitted by securities laws and other legal requirements, including provisions in our credit agreement placing limitations on such repurchases. The repurchase programs have been and will be funded from our operations.