CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
Feb. 08, 2018	Dec. 31, 2018	Dec. 31, 2019
Revenue
Operating revenue	$ 40,136	$ 473,473	$ 500,220
Gain on sale of assets	840	4,751	1,382
Gain (loss) on derivatives	6,663	(10,247)	(11,744)
Total revenue	47,639	467,977	489,858
Operating expenses
Lease operating	4,408	56,827	63,755
Transportation, processing and marketing	3,725	19,293	21,042
Midstream operating	0	15,221	24,719
Cost of sales for purchased gathered production	0	31,247	34,529
Production taxes	953	16,865	19,455
Workovers	423	5,563	3,189
Exploration	7,003	34,085	52,354
Depreciation, depletion and amortization	11,670	160,942	132,292
Impairment of assets	0	3,205,051	905,293
General and administrative	21,234	131,052	107,655
Total operating expenses	49,416	3,676,146	1,364,283
Operating income	(1,777)	(3,208,169)	(874,425)
Other income (expense)
Interest expense	(5,511)	(43,296)	(61,459)
Interest income and other	172	2,049	243
Equity in earnings of unconsolidated subsidiaries	0	0	6,216
Reorganization items, net	0	0	(197)
Total other income (expense), net	(5,339)	(41,247)	(55,197)
Loss from continuing operations before income taxes	(7,116)	(3,249,416)	(929,622)
Income tax expense (benefit)	0	(69)	0
Loss from continuing operations	(7,116)	(3,249,347)	(929,622)
Loss from discontinued operations, net of tax	(7,746)	0	0
Net loss	(14,862)	(3,249,347)	(929,622)
Net loss attributable to non-controlling interest		(1,724,648)	(479,084)
Net loss attributable to Alta Mesa Resources, Inc. stockholders	(14,862)	$ (1,524,699)	$ (450,538)
Net loss per common share attributable to Alta Mesa Resources, Inc. stockholders:
Basic and diluted (in dollars per share)		$ (8.71)	$ (2.48)
Oil
Revenue
Operating revenue	30,972	$ 323,299	$ 328,386
Natural gas
Revenue
Operating revenue	4,276	43,407	53,693
Natural gas liquids
Revenue
Operating revenue	4,000	43,039	40,026
Sales of gathered production
Revenue
Operating revenue	0	31,506	37,195
Midstream revenue
Revenue
Operating revenue	0	27,460	30,590
Other
Revenue
Operating revenue	$ 888	$ 4,762	$ 10,330

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Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells.

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