Represents the term of the transportation precedent agreement.

No definition available.

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- Details

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Namespace Prefix:	eqt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the length of Federal Energy Regulatory Commission (FERC) regulated transmission pipeline.

+ References

No definition available.

+ Details

Name:	eqt_GasAndOilLengthOfPipeline
Namespace Prefix:	eqt_
Data Type:	num:lengthItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount the entity agreed to spend under the long-term purchase commitment after five years following the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The amount the entity agreed to spend under the long-term purchase commitment within the fifth year following the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The amount the entity agreed to spend under the long-term purchase commitment within the fourth year following the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The amount the entity agreed to spend under the long-term purchase commitment within the third year following the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The amount the entity agreed to spend under the long-term purchase commitment within the second year following the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The amount the entity agreed to spend under the long-term purchase commitment in the next year.

+ References

No definition available.

+ Details

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

- Details

Name:	eqt_PipelineDemandChargesAbstract
Namespace Prefix:	eqt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Transmission and Storage System Capacity

+ References

No definition available.

+ Details

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

- Definition

Transmission Capacity

+ References

No definition available.

+ Details

Name:	eqt_TransmissionCapacity
Namespace Prefix:	eqt_
Data Type:	num:energyItemType
Balance Type:	na
Period Type:	duration

- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

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-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

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

- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Balance Type:	credit
Period Type:	instant

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Name:	us-gaap_OperatingLeasesRentExpenseAbstract
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- Details

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Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			0 Months Ended		1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 24, 2014 MMBTU mi	Sep. 02, 2014 mi MMcf	Sep. 30, 2014 mi
Operating Leases, Rent
Operating leases, rent expense	$ 65.6us-gaap_LeaseAndRentalExpense	$ 56.0us-gaap_LeaseAndRentalExpense	$ 45.0us-gaap_LeaseAndRentalExpense
Amount due in 2014	225.6
Amount due in 2015	83.4
Amount due in 2016	37.4
Amount due in 2017	31.7
Amount due in 2018	16.8
Amount due in 2019	9.6
Amount due thereafter	46.7
Remedial action included in other credits	1.3
OVC Pipeline
Operating Leases, Rent
Gas and Oil Length of Pipeline				36
Term of agreement				20 years
Transmission capacity (in MMBtu per day)				650,000
Mountain Valley Pipeline
Operating Leases, Rent
Gas and Oil Length of Pipeline					300	300
Term of agreement				20 years
Transmission firm capacity (in MMcf per day)					2,000
Pipeline demand charges
Drilling Equipment and Services Supply Agreements [Abstract]
Amount due as of the balance sheet date	4,632.2
Amount due in 2015	205.1
Amount due in 2016	267.8
Amount due in 2017	333.1
Amount due in 2018	353.4
Amount due in 2019	348.0
Amount due thereafter	3,124.8
Pipeline Demand Charges [Abstract]
Amount due as of the balance sheet date	4,632.2
Drilling equipment and services supply agreements
Drilling Equipment and Services Supply Agreements [Abstract]
Amount due as of the balance sheet date	132.0
Pipeline Demand Charges [Abstract]
Amount due as of the balance sheet date	$ 132.0