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Property and Equipment - Summary of Oil and Gas Properties Not Subject to Amortization (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Property, Plant and Equipment [Line Items] |  |  |  |
Acquisition costs | $ 1,511,685 | $ 129,741 | $ 429,897 | $ 824,363
Acquisition costs, total | 2,895,686 |  |  |
Exploration costs | 0 | 0 | 0 | 0
Exploration costs, total | 0 |  |  |
Development costs | 5,076 | 4,607 | 3,635 | 2,214
Development costs, total | 15,532 |  |  |
Capitalized interest | 3,871 | (536) | (1,141) | (438)
Capitalized interest, total | 1,756 |  |  |
Total oil and natural gas properties not subject to amortization | 1,520,632 | 133,812 | $ 432,391 | $ 826,139
Total oil and natural gas properties not subject to amortization, total | 2,912,974 | $ 1,580,305 |  |
Utica |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | 1,513,452 |  |  |
MidContinent |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | 1,396,642 |  |  |
Niobrara |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | 2,184 |  |  |
Southern Louisiana |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | 552 |  |  |
Bakken |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | 99 |  |  |
Other |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Total oil and natural gas properties not subject to amortization, total | $ 45 |  |  |

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- Definition The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(3)(ii)(A)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The sum of the capitalized costs incurred during the period of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The capitalized costs incurred during the period (excluded from amortization) to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(a)(7)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(3)(ii)(A)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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- Definition The capitalized costs incurred during the period (excluded from amortization) 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: 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. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(3)(ii)(A)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(a)(12)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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