Capital Stock	12 Months Ended
Dec. 31, 2014
Equity [Abstract]
Capital Stock	Capital Stock Incentive Plans On May 1, 2014, the Company’s shareholders approved the 2014 Incentive Plan, which replaced the 2004 Incentive Plan that expired on April 29, 2014. Under the 2014 Incentive Plan, incentive and non-statutory stock options, stock appreciation rights (SARs), stock awards, cash awards and performance awards may be granted to key employees, consultants and officers of the Company. Non-employee directors of the Company may be granted discretionary awards under the 2014 Incentive Plan consisting of stock options or stock awards. A total of 18 million shares of common stock may be issued under the 2014 Incentive Plan. Under the 2014 Incentive Plan, no more than 10 million shares may be issued pursuant to incentive stock options. No additional awards may be granted under the 2014 Incentive Plan on or after May 1, 2024. At December 31, 2014, approximately 18.0 million shares are available for issuance under the plan. No additional awards will be granted under any of the Company’s prior plans, including the 2004 Incentive Plan. Awards outstanding under the 2004 Incentive Plan will remain outstanding in accordance with their original terms and conditions. Increase in Authorized Shares In May 2014, the Company’s shareholders approved an increase in the authorized number of shares of common stock from 480 million to 960 million shares. Treasury Stock In August 1998, the Board of Directors authorized a share repurchase program under which the Company may purchase shares of common stock in the open market or in negotiated transactions. The timing and amount of these stock purchases are determined at the discretion of management. The Company may use the repurchased shares to fund stock compensation programs presently in existence, or for other corporate purposes. All purchases executed to date have been through open market transactions. There is no expiration date associated with the authorization to repurchase shares of the Company. During the year ended December 31, 2014 and 2013, the Company repurchased 4.3 million shares for a total cost of $138.9 million and 4.8 million shares for a total cost of $164.6 million, respectively. There were no share repurchases in 2012. Since the authorization date, the Company has repurchased 29.9 million shares of the 40.0 million total shares authorized, of which 20.0 million shares have been retired, for a total cost of approximately $388.4 million. No treasury shares have been delivered or sold by the Company subsequent to the repurchase. As of December 31, 2014, 9.9 million shares were held as treasury stock. Dividend Restrictions The Board of Directors of the Company determines the amount of future cash dividends, if any, to be declared and paid on the common stock depending on, among other things, the Company's financial condition, funds from operations, the level of its capital and exploration expenditures, and its future business prospects. None of the fixed rate note or credit agreements in place have restricted payment provisions or other provisions limiting dividends.

Capital Stock

12 Months Ended

Dec. 31, 2014

Incentive Plans

On May 1, 2014, the Company’s shareholders approved the 2014 Incentive Plan, which replaced the 2004 Incentive Plan that expired on April 29, 2014. Under the 2014 Incentive Plan, incentive and non-statutory stock options, stock appreciation rights (SARs), stock awards, cash awards and performance awards may be granted to key employees, consultants and officers of the Company. Non-employee directors of the Company may be granted discretionary awards under the 2014 Incentive Plan consisting of stock options or stock awards. A total of 18 million shares of common stock may be issued under the 2014 Incentive Plan. Under the 2014 Incentive Plan, no more than 10 million shares may be issued pursuant to incentive stock options. No additional awards may be granted under the 2014 Incentive Plan on or after May 1, 2024. At December 31, 2014, approximately 18.0 million shares are available for issuance under the plan.

No additional awards will be granted under any of the Company’s prior plans, including the 2004 Incentive Plan. Awards outstanding under the 2004 Incentive Plan will remain outstanding in accordance with their original terms and conditions.

Increase in Authorized Shares

In May 2014, the Company’s shareholders approved an increase in the authorized number of shares of common stock from 480 million to 960 million shares.

Treasury Stock

In August 1998, the Board of Directors authorized a share repurchase program under which the Company may purchase shares of common stock in the open market or in negotiated transactions. The timing and amount of these stock purchases are determined at the discretion of management. The Company may use the repurchased shares to fund stock compensation programs presently in existence, or for other corporate purposes. All purchases executed to date have been through open market transactions. There is no expiration date associated with the authorization to repurchase shares of the Company.

During the year ended December 31, 2014 and 2013, the Company repurchased 4.3 million shares for a total cost of $138.9 million and 4.8 million shares for a total cost of $164.6 million, respectively. There were no share repurchases in 2012. Since the authorization date, the Company has repurchased 29.9 million shares of the 40.0 million total shares authorized, of which 20.0 million shares have been retired, for a total cost of approximately $388.4 million. No treasury shares have been delivered or sold by the Company subsequent to the repurchase. As of December 31, 2014, 9.9 million shares were held as treasury stock.

Dividend Restrictions

The Board of Directors of the Company determines the amount of future cash dividends, if any, to be declared and paid on the common stock depending on, among other things, the Company's financial condition, funds from operations, the level of its capital and exploration expenditures, and its future business prospects. None of the fixed rate note or credit agreements in place have restricted payment provisions or other provisions limiting dividends.