Capital transactions	9 Months Ended
Sep. 30, 2011
Capital Transactions Disclosure [Abstract]
Capital transactions	13. Capital transactions Repurchase Program On February 3, 2011, our Board of Directors authorized a new stock repurchase program (the “2011 Stock Repurchase Program”) under which we may repurchase up to $1.5 billion of our common stock, on terms and conditions to be determined by the Company, until the earlier of March 31, 2012 and a determination by the Board of Directors to discontinue the repurchase program. During the nine months ended September 30, 2011, we repurchased 45 million shares of our common stock for $502 million pursuant to the 2011 Stock Repurchase Program. Additionally, in October 2011, we settled the purchase of 0.5 million shares of our common stock that we had committed to repurchase in September 2011 pursuant to this program for $6 million. On February 10, 2010, our Board of Directors authorized a stock repurchase program (the “2010 Stock Repurchase Program”) under which we were authorized to repurchase up to $1 billion of our common stock. The 2010 Stock Repurchase Program expired on December 31, 2010. In January 2011, we settled a $22 million purchase of 1.8 million shares of our common stock that we had committed to repurchase in December 2010 pursuant to the 2010 Stock Repurchase Program. Dividend On February 9, 2011, our Board of Directors approved a cash dividend of $0.165 per common share to be paid on May 11, 2011 to shareholders of record as of March 16, 2011, and on May 11, 2011, we made a cash dividend payment of $192 million to such shareholders. On August 12, 2011, the Company made dividend equivalent payments of $2 million related to this cash dividend to the holders of restricted stock units.

Capital transactions

9 Months Ended

Sep. 30, 2011

Capital Transactions Disclosure [Abstract]

13. Capital transactions

Repurchase Program

On February 3, 2011, our Board of Directors authorized a new stock repurchase program (the “2011 Stock Repurchase Program”) under which we may repurchase up to $1.5 billion of our common stock, on terms and conditions to be determined by the Company, until the earlier of March 31, 2012 and a determination by the Board of Directors to discontinue the repurchase program. During the nine months ended September 30, 2011, we repurchased 45 million shares of our common stock for $502 million pursuant to the 2011 Stock Repurchase Program. Additionally, in October 2011, we settled the purchase of 0.5 million shares of our common stock that we had committed to repurchase in September 2011 pursuant to this program for $6 million.

On February 10, 2010, our Board of Directors authorized a stock repurchase program (the “2010 Stock Repurchase Program”) under which we were authorized to repurchase up to $1 billion of our common stock. The 2010 Stock Repurchase Program expired on December 31, 2010. In January 2011, we settled a $22 million purchase of 1.8 million shares of our common stock that we had committed to repurchase in December 2010 pursuant to the 2010 Stock Repurchase Program.

Dividend

On February 9, 2011, our Board of Directors approved a cash dividend of $0.165 per common share to be paid on May 11, 2011 to shareholders of record as of March 16, 2011, and on May 11, 2011, we made a cash dividend payment of $192 million to such shareholders. On August 12, 2011, the Company made dividend equivalent payments of $2 million related to this cash dividend to the holders of restricted stock units.