Capital Stock	12 Months Ended
Dec. 31, 2017
Capital Stock [Abstract]
Capital Stock	Capital Stock Dividends During 2017, 2016 and 2015 we paid cash dividends of $110 million, $82 million and $68 million, respectively, on our common stock. On January 16, 2018, the Company’s Board of Directors (or a duly authorized committee thereof) declared cash dividends of $0.14 per share on our common stock, or approximately $34 million in the aggregate. The cash dividend will be paid on March 1, 2018 to stockholders of record as of the close of business on February 1, 2018. Future quarterly dividends are subject to Board approval. Common Stock Repurchases On September 18, 2013, the Board of Directors approved our common stock repurchase program. From time to time, the Board of Directors has approved increases in the amount authorized to be purchased under that program. On February 2, 2017, the Board of Directors approved a further increase in that authorization to $2.1 billion. This program expires on December 31, 2019. We intend to repurchase shares of common stock in open market transactions in order to offset new shares issued under equity compensation programs and to provide for additional shareholder returns. During 2017, we repurchased 12,755,547 shares at an average price, including commissions, of $31.37 per share, or $400 million in the aggregate. Since 2013, we repurchased 43,969,657 shares at an average price, including commissions, of $29.87 per share, or $1,313 million in the aggregate. In addition, we may repurchase shares delivered to us by employees as payment for the exercise price of stock options and the withholding taxes due upon the exercise of stock options or the vesting or payment of stock awards. During 2017, we did not repurchase any shares from employees.

Capital Stock

Dividends

During 2017, 2016 and 2015 we paid cash dividends of $110 million, $82 million and $68 million, respectively, on our common stock. On January 16, 2018, the Company’s Board of Directors (or a duly authorized committee thereof) declared cash dividends of $0.14 per share on our common stock, or approximately $34 million in the aggregate. The cash dividend will be paid on March 1, 2018 to stockholders of record as of the close of business on February 1, 2018. Future quarterly dividends are subject to Board approval.

Common Stock Repurchases

On September 18, 2013, the Board of Directors approved our common stock repurchase program. From time to time, the Board of Directors has approved increases in the amount authorized to be purchased under that program. On February 2, 2017, the Board of Directors approved a further increase in that authorization to $2.1 billion. This program expires on December 31, 2019. We intend to repurchase shares of common stock in open market transactions in order to offset new shares issued under equity compensation programs and to provide for additional shareholder returns. During 2017, we repurchased 12,755,547 shares at an average price, including commissions, of $31.37 per share, or $400 million in the aggregate. Since 2013, we repurchased 43,969,657 shares at an average price, including commissions, of $29.87 per share, or $1,313 million in the aggregate.

In addition, we may repurchase shares delivered to us by employees as payment for the exercise price of stock options and the withholding taxes due upon the exercise of stock options or the vesting or payment of stock awards. During 2017, we did not repurchase any shares from employees.