CONDENSED CONSOLIDATED BALANCE SHEET (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 241,394	$ 2,287
Accounts receivable, net	183,376	362,403
Income taxes receivable	121,859	109,251
Inventories	19,381	11,076
Derivative instruments	61,194	57,665
Other current assets	4,126	1,863
Total current assets	631,330	544,545
Properties and equipment, net (Successful efforts method)	3,699,575	3,463,606
Equity method investments	166,138	163,181
Other assets	66,686	27,497
TOTAL ASSETS	4,563,729	4,198,829
Current liabilities
Accounts payable	184,960	241,939
Accrued liabilities	29,184	25,227
Interest payable	19,882	20,098
Total current liabilities	234,026	287,264
Long-term debt, net	1,219,555	1,226,104
Deferred income taxes	611,163	458,597
Asset retirement obligations	54,356	50,622
Postretirement benefits	28,874	27,912
Other liabilities	70,951	60,171
Total liabilities	2,218,925	2,110,670
Commitments and contingencies
Stockholders' equity
Common stock	47,688	47,610
Additional paid-in capital	1,769,195	1,763,142
Retained earnings	1,983,733	1,607,658
Accumulated other comprehensive income	4,164	4,437
Treasury Stock	(1,459,976)	(1,334,688)
Total stockholders' equity	2,344,804	2,088,159
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 4,563,729	$ 4,198,829

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).