CONDENSED CONSOLIDATED BALANCE SHEET (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 15,231	$ 20,954
Accounts receivable, net	138,354	239,009
Inventories	20,423	14,026
Derivative instruments	76,178	137,603
Other current assets	4,807	1,855
Total current assets	254,993	413,447
Properties and equipment, net (Successful efforts method)	5,132,655	4,925,711
Equity method investments	81,075	68,029
Other assets	36,197	30,529
TOTAL ASSETS	5,504,920	5,437,716
Current liabilities
Accounts payable	218,633	400,076
Accrued liabilities	57,465	63,669
Deferred income taxes	2,754	35,273
Total current liabilities	278,852	499,018
Postretirement benefits	37,314	35,827
Long-term debt	1,995,000	1,752,000
Deferred income taxes	878,069	843,876
Asset retirement obligations	134,763	124,655
Other liabilities	35,006	39,607
Total liabilities	$ 3,359,004	$ 3,294,983
Commitments and contingencies
Stockholders' equity
Common stock: Authorized -- 960,000,000 shares of $0.10 par value in 2015 and 2014, respectively Issued-- 423,700,648 shares and 422,915,258 shares in 2015 and 2014, respectively	$ 42,370	$ 42,292
Additional paid-in capital	717,327	710,432
Retained earnings	1,695,205	1,698,995
Accumulated other comprehensive income (loss)	(2,151)	(2,151)
Less treasury stock, at cost: 9,892,680 shares in 2015 and 2014, respectively	(306,835)	(306,835)
Total stockholders' equity	2,145,916	2,142,733
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 5,504,920	$ 5,437,716