This element represents the percentage of the stock-based award which will vest at the end of year one.

No definition available.

Name:	eqt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAtEndOfOneYearInPercentage
Namespace Prefix:	eqt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This element represents the percentage of the stock-based award which will vest at the end of year two.

+ References

No definition available.

+ Details

Name:	eqt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAtEndOfTwoYearInPercentage
Namespace Prefix:	eqt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the payout percentage based upon the performance during the performance period.

+ References

No definition available.

+ Details

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

- Definition

The stated exercise price for purposes of disclosing shares potentially issuable under outstanding stock option awards on stock option plans.

+ References

No definition available.

+ Details

Name:	eqt_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePrice
Namespace Prefix:	eqt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to be Distributed in Common Stock

+ References

No definition available.

+ Details

Name:	eqt_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsExpectedtobeDistributedinCommonStock
Namespace Prefix:	eqt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to be Paid in Cash

+ References

No definition available.

+ Details

Name:	eqt_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsExpectedtobePaidinCash
Namespace Prefix:	eqt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- 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

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

- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=eqt_NonqualifiedStockOptionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=eqt_RestrictedStockUnitsLiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=eqt_A2018ValueDriverPerformanceShareUnitAwardProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=eqt_A2018IncentivePerformanceShareUnitProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Share-Based Compensation Plans - 2018 Awards (Details) - $ / shares		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Non-qualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		153,700
Weighted average remaining contractual term, outstanding		6 years 3 months
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)		2,375,584
Restricted Stock Units, Liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)		292,400	148,860
Period after which the shares granted will be fully vested		3 years
Subsequent Event \| Non-qualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period after which the shares granted will be fully vested	3 years
Granted (in shares)	287,800
Weighted average remaining contractual term, outstanding	10 years
Exercise price (in dollars per share)	$ 56.92
Subsequent Event \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	86,200
Period after which the shares granted will be fully vested	3 years
Subsequent Event \| Restricted Stock Units, Liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	264,930
Subsequent Event \| 2018 Value Driver Performance Share Unit Award Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	363,460
Award vested at end of year one	50.00%
Award vested at end of year two	50.00%
Subsequent Event \| 2018 Value Driver Performance Share Unit Award Program \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation plan, award as a percentage of target award level	0.00%
Subsequent Event \| 2018 Value Driver Performance Share Unit Award Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation plan, award as a percentage of target award level	300.00%
Subsequent Event \| 2018 Incentive Performance Share Unit Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	314,210
Period after which the shares granted will be fully vested	3 years
Expected to be distributed in common stock (in shares)	172,350
Expected to be paid in cash (in shares)	141,860
Subsequent Event \| 2018 Incentive Performance Share Unit Program \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation plan, award as a percentage of target award level	0.00%
Subsequent Event \| 2018 Incentive Performance Share Unit Program \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation plan, award as a percentage of target award level	300.00%