Represents the area of property transferred under an agreement.

No definition available.

Name:	eqt_AreaOfPropertyTransferredUnderAgreement
Namespace Prefix:	eqt_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

The approximate area of acquisition by the entity.

+ References

No definition available.

+ Details

Name:	eqt_AssetAcquisitionAreaOfProperty
Namespace Prefix:	eqt_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of producing wells acquired under an agreement.

+ References

No definition available.

+ Details

Name:	eqt_AssetAcquisitionNumberOfProducingWells
Namespace Prefix:	eqt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the carrying value of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_EnergyMarketingContractsCarryingValue
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the gain (loss) from sale of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_GainLossOnSaleOfEnergyMarketingContracts
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the number of customers with whom sale agreements are entered.

+ References

No definition available.

+ Details

Name:	eqt_NumberOfCustomersWithWhomSalesAgreementsEntered
Namespace Prefix:	eqt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of customers with whom sale agreements are entered related to certain acquired assets.

+ References

No definition available.

+ Details

Name:	eqt_NumberOfCustomersWithWhomSalesAgreementsEnteredRelatedToCertainAcquiredAssets
Namespace Prefix:	eqt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of producing wells transferred under the agreement.

+ References

No definition available.

+ Details

Name:	eqt_NumberOfProducingWellsTransferredUnderAgreement
Namespace Prefix:	eqt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of ownership interest transferred under the agreement.

+ References

No definition available.

+ Details

Name:	eqt_PercentageOfOwnershipInterestTransferredUponCompletionOfTransaction
Namespace Prefix:	eqt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow associated with the sale of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_ProceedsFromSaleOfEnergyMarketingContracts
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount expected to be collected from the sale of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_ReceivableFromSaleOfEnergyMarketingContracts
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the cash inflow from sale of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_SaleOfEnergyMarketingContracts
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the sale of energy marketing contracts related to certain acquired assets.

+ References

No definition available.

+ Details

Name:	eqt_SaleOfEnergyMarketingContractsRelatedToCertainAcquiredAssets
Namespace Prefix:	eqt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the sale volumes of energy marketing contracts.

+ References

No definition available.

+ Details

Name:	eqt_SaleVolumesOfEnergyMarketingContracts
Namespace Prefix:	eqt_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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

- Definition

Amount of gain (loss) on sale or disposal of oil and gas property or timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainLossOnSaleOfProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow to purchase of mineral interests in oil and gas properties for use in the normal oil and gas operations and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireOilAndGasProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Definition

The value of all consideration given or received by the Entity in the significant acquisition or disposal.

+ References

No definition available.

+ Details

Name:	us-gaap_SignificantAcquisitionsAndDisposalsAcquisitionCostsOrSaleProceeds
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_CounterpartyNameAxis=eqt_RangeResourcesCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=eqt_EquitableGasAndHomeworksMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=eqt_NoraLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=eqt_EQTProductionMember
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Sales of Properties and Contracts (Details) (USD $)	0 Months Ended	12 Months Ended
Sales of Properties and Contracts (Details) (USD $)	Jun. 16, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 17, 2013
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of energy marketing contracts in cash		$ 0	$ 23,000,000	$ 0
Pre-tax gain recorded		34,146,000us-gaap_GainLossOnSaleOfProperty	19,618,000us-gaap_GainLossOnSaleOfProperty	0us-gaap_GainLossOnSaleOfProperty
Pre-tax gain on de-designation of derivative instruments	28,000,000
Nora Gathering, LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	0.00%
EQT
Schedule of Equity Method Investments [Line Items]
Pre-tax gain recorded		27,400,000
Range Resources Corporation
Schedule of Equity Method Investments [Line Items]
Approximate area of acquisition (in acres)	73,000
Number of producing wells acquired	900
Area of property transferred under asset exchange agreement (in acres)	138,000
Number of producing wells transferred under asset exchange agreement	2,000
Ownership interest transferred	50.00%
Fair value of the consideration acquired	516,500,000
Pre-tax gain recorded	34,100,000
Range Resources Corporation \| Acreage
Schedule of Equity Method Investments [Line Items]
Fair value of the consideration acquired	318,300,000
Range Resources Corporation \| Wells
Schedule of Equity Method Investments [Line Items]
Fair value of the consideration acquired	198,200,000
Range Resources Corporation \| EQT
Schedule of Equity Method Investments [Line Items]
Amount of cash, subject to certain post-closing adjustments	167,300,000
Range Resources Corporation \| EQT \| Nora Gathering, LLC
Schedule of Equity Method Investments [Line Items]
Amount of cash, subject to certain post-closing adjustments	167,300,000
Ownership percentage		50.00%
Pre-tax gain recorded		6,800,000
Equitable Gas and Homeworks
Schedule of Equity Method Investments [Line Items]
Sale of energy marketing contracts			20,000,000
Number of customers with whom natural gas sale agreements are entered			1,000
Sale volumes of energy marketing contracts (in Mcf)			12,000
Proceeds from sale of energy marketing contracts in cash			18,000,000
Amount expected to be collected			2,000,000
Gain on sale of energy marketing contracts			19,600,000
Number of customers with whom natural gas sale agreements are entered related to certain acquired assets			50
Value of energy marketing contracts					5,000,000
Sale of energy marketing contracts related to certain acquired assets			$ 5,000,000