CONDENSED CONSOLIDATED BALANCE SHEET - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 202,842	$ 200,227
Restricted cash	11,595	13,556
Accounts receivable, net	135,697	209,023
Income taxes receivable	156,551	129,795
Inventories	18,249	13,932
Derivative instruments	16,085	31
Other current assets	770	1,684
Total current assets	541,789	568,248
Properties and equipment, net (Successful efforts method)	3,920,497	3,855,706
Other assets	59,889	63,291
TOTAL ASSETS	4,522,175	4,487,245
Current liabilities
Accounts payable	183,816	189,811
Current portion of long-term debt	175,000	87,000
Accrued liabilities	21,409	31,290
Interest payable	6,952	19,933
Total current liabilities	387,177	328,034
Long-term debt, net	1,045,260	1,133,025
Deferred income taxes	746,108	702,104
Asset retirement obligations	77,029	71,598
Postretirement benefits	33,130	32,713
Other liabilities	65,076	68,284
Total liabilities	2,353,780	2,335,758
Commitments and contingencies
Stockholders' equity
Common stock	47,753	47,688
Additional paid-in capital	1,785,313	1,782,427
Retained earnings	2,157,306	2,143,213
Accumulated other comprehensive income	1,224	1,360
Treasury stock	(1,823,201)	(1,823,201)
Total stockholders' equity	2,168,395	2,151,487
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 4,522,175	$ 4,487,245