Equity

6 Months Ended

Jun. 30, 2011

Equity and Comprehensive Income [Abstract]

Equity

12.   Equity

Preferred Stock

In March 2011, the remaining 8,221 shares of our Series A Preferred Stock were converted into 493,260 shares of common stock by the holder pursuant to the conversion terms of the Series A Preferred Stock. As of June 30, 2011, there are no shares of preferred stock issued and outstanding.

Share Repurchases

In February 2011, our Board of Directors authorized the repurchase of up to 20.0 million shares of our common stock. We expect to use this repurchase program principally to offset common stock issued under our share-based compensation plans. This repurchase program does not have an expiration date. Under this authorization, we repurchased approximately 2.2 million and 5.0 million shares of our common stock at a cost of $191.3 million and $386.6 million, respectively, during the three and six months ended June 30, 2011.

For the three and six months ended June 30, 2010, we repurchased approximately 20.8 million and 31.3 million shares at a cost of approximately $1.0 billion and $1.6 billion, respectively, under our 2010 and 2009 stock repurchase authorizations. We retired all of these shares as they were acquired. In connection with this retirement, in accordance with our policy, we recorded a reduction in additional paid-in-capital by the same amount.