- Definition

The cap rate on a price risk derivative such as a cap or collar. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

Floor rate on a price risk derivative such as a floor or a collar. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeSwapTypeAverageFixedPrice
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cog_CruedOilCollarWithContractPeriodofJanuary2018toDecember2018Member
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Derivative Instruments and Hedging Activities - Outstanding Commodity Derivatives (Details) MMBbls in Millions, Bcf in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2018 $ / Mcf Bcf	Dec. 31, 2017 $ / bbl $ / Mcf MMBbls Bcf
Natural gas (Leidy)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf		17.7
Natural gas (Leidy) \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf		0.71
Natural gas (Transco)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf		21.3
Natural gas (Transco) \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf		0.42
Crude oil (WTI/LLS)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| MMBbls		2.9
Crude oil (WTI/LLS) \| Minimum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl		63.35
Crude oil (WTI/LLS) \| Maximum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl		63.80
Crude oil (WTI/LLS) \| Weighted Average
Derivative [Line Items]
Collar Floor Price (in usd per Mcf or usd per bbl) \| $ / bbl		55.00
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl		63.62
Natural gas purchase
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf		81.2
Natural gas purchase \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf		3.70
Natural gas sales
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf		11.7
Natural gas sales \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf		4.71
Subsequent Event \| Natural gas (NYMEX)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf	84.4
Subsequent Event \| Natural gas (NYMEX) \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf	2.93
Subsequent Event \| Natural gas (NYMEX)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf	13.3
Subsequent Event \| Natural gas (NYMEX) \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf	3.10
Subsequent Event \| Natural gas (Leidy)
Derivative [Line Items]
Volume (in Bcf for gas and Mmbbls for oil) \| Bcf	16.2
Subsequent Event \| Natural gas (Leidy) \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf or usd per bbl) \| $ / Mcf	0.68