Subsequent Events	6 Months Ended
Jun. 30, 2012
Subsequent Events	13. Subsequent Events The Company has evaluated the period after the balance sheet date, noting no subsequent events or transactions that required recognition or disclosure in the financial statements, other than as noted below. Senior unsecured notes. On July 2, 2012, the Company issued $400 million of 6.875% senior unsecured notes due January 15, 2023 (the “2023 Notes”). Interest is payable on the 2023 Notes semi-annually in arrears on January 15 and July 15 of each year, beginning on January 15, 2013. The 2023 Notes are jointly and severally guaranteed on a senior unsecured basis by all of the Company’s existing material subsidiaries. The issuance of the 2023 Notes resulted in net proceeds to the Company of approximately $392 million, which the Company will use to fund its exploration, development and acquisition program and for general corporate purposes. The issuance and sale of the 2023 Notes has been registered under the Securities Act of 1933 pursuant to an automatic shelf Registration Statement on Form S-3 (Registration No. 333-175603), as amended, of the Company, filed with the SEC on July 15, 2011. Derivative instruments. In July 2012, the Company entered into new two-way costless collar options, all of which settle monthly based on the West Texas Intermediate crude oil index price, for a total notional amount of 183,000 barrels in 2012, 1,215,500 barrels in 2013 and 108,500 barrels in 2014. These derivative instruments do not qualify for and were not designated as hedging instruments for accounting purposes.

13. Subsequent Events

The Company has evaluated the period after the balance sheet date, noting no subsequent events or transactions that required recognition or disclosure in the financial statements, other than as noted below.

Senior unsecured notes. On July 2, 2012, the Company issued $400 million of 6.875% senior unsecured notes due January 15, 2023 (the “2023 Notes”). Interest is payable on the 2023 Notes semi-annually in arrears on January 15 and July 15 of each year, beginning on January 15, 2013. The 2023 Notes are jointly and severally guaranteed on a senior unsecured basis by all of the Company’s existing material subsidiaries. The issuance of the 2023 Notes resulted in net proceeds to the Company of approximately $392 million, which the Company will use to fund its exploration, development and acquisition program and for general corporate purposes. The issuance and sale of the 2023 Notes has been registered under the Securities Act of 1933 pursuant to an automatic shelf Registration Statement on Form S-3 (Registration No. 333-175603), as amended, of the Company, filed with the SEC on July 15, 2011.

Derivative instruments. In July 2012, the Company entered into new two-way costless collar options, all of which settle monthly based on the West Texas Intermediate crude oil index price, for a total notional amount of 183,000 barrels in 2012, 1,215,500 barrels in 2013 and 108,500 barrels in 2014. These derivative instruments do not qualify for and were not designated as hedging instruments for accounting purposes.