Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 35
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66906256&loc=d3e66150-109466

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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- Details

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- Details

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Name:	srt_StatementGeographicalAxis=cog_WestVirginiaVirginiaandOhioMember
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Name:	srt_StatementGeographicalAxis=cog_EastTexasMember
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Divestitures - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended				12 Months Ended
Divestitures - Narrative (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Feb. 28, 2018	Sep. 30, 2017	Feb. 29, 2016	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant Acquisitions and Disposals
Loss on sale of assets									$ 16,327	$ 11,565	$ 1,857
Proceeds from sale of assets									678,350	115,444	50,419
Impairment of oil and gas properties									$ 0	$ 482,811	$ 435,619
Oil and gas properties, proved and unproved \| Haynesville Shale
Significant Acquisitions and Disposals
Loss on sale of assets						$ (29,700)
Proceeds from sale of assets	$ 30,000					5,000
Oil and gas properties, proved and unproved \| Eagle Ford Shale
Significant Acquisitions and Disposals
Loss on sale of assets					$ 45,400
Proceeds from sale of assets		$ 765,000
Impairment of oil and gas properties						$ 414,300
Oil and gas properties, proved and unproved \| West Virginia, Virginia, and Ohio
Significant Acquisitions and Disposals
Loss on sale of assets			$ 11,900
Proceeds from sale of assets			$ 41,300
Impairment of oil and gas properties							$ 68,600
Oil and gas properties, proved and unproved \| East Texas
Significant Acquisitions and Disposals
Loss on sale of assets				$ (500)
Proceeds from sale of assets				$ 56,400				$ 6,300