Stock Repurchases

12 Months Ended

Dec. 31, 2015

Stockholders' Equity Note [Abstract]

Stock Repurchases

Stock Repurchases:

Our Board of Directors has authorized a total of $1.4 billion towards the repurchase of shares of our common stock (collectively referred to as the "Share Repurchase Plans"), including a $700.0 million share repurchase authorization in October 2014, and a $300.0 million share repurchase authorization in December 2012. The Share Repurchase Plans authorize open market repurchase transactions and do not have a stated expiration date. As of December 31, 2015, $396.2 million of shares may still be repurchased under the Share Repurchase Plans.

On October 20, 2014, we announced our plans for a new $450.0 million accelerated share repurchase program (the "ASR"). For the years ended December 31, 2015 and 2014, the final number of shares repurchased under the Share Repurchase Plans, including repurchases under the ASR, was 0.5 million shares in 2015 and 5.2 million in 2014 for a total of $550.3 million.

We also repurchased 0.3 million shares for $32.0 million and 0.2 million shares for $22.4 million for the years ended December 31, 2015 and 2014, respectively, from employees who surrendered their shares to satisfy minimum tax withholding obligations upon the vesting of stock-based compensation awards.