Weighted average interest rate of debt outstanding.

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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

- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

+ Details

Name:	us-gaap_WriteOffOfDeferredDebtIssuanceCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Balance Type:
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- Details

Name:	dei_LegalEntityAxis=eqt_EQTMidstreamPartnersLPMember
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Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=eqt_EQT2.5BillionFacilityMember
Namespace Prefix:
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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=eqt_RMP850MillionFacilityMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=eqt_EQMTermLoanFacilityMember
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Revolving Credit Facilities (Details) - USD ($)		1 Months Ended	2 Months Ended	3 Months Ended		7 Months Ended	9 Months Ended
Revolving Credit Facilities (Details) - USD ($)	Jul. 23, 2018	Jul. 23, 2018	Jun. 25, 2018	Sep. 30, 2018	Sep. 30, 2017	Jul. 23, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Apr. 25, 2018	Dec. 31, 2017
Revolving credit facility \| EQM
Line of Credit Facility
Line of credit facility, maximum borrowing capacity				$ 1,000,000,000			$ 1,000,000,000
Amount of borrowings				22,000,000			22,000,000				$ 180,000,000
Letters of credit outstanding under revolving credit facility				1,000,000			1,000,000				0
Maximum amount of outstanding short-term loans at any time during the period				74,000,000	$ 177,000,000		420,000,000	$ 177,000,000
Average daily balance of short-term loans outstanding during the period				$ 22,000,000	$ 95,000,000		$ 147,000,000	$ 32,000,000
Weighted average interest rates of average daily balance of short-term loans				3.70%	2.70%		3.20%	2.70%
Repayments of lines of credit	$ 260,000,000
Revolving credit facility \| EQM \| Scenario, Forecast
Line of Credit Facility
Line of credit facility, maximum borrowing capacity									$ 3,000,000,000
Revolving credit facility \| EQT 2.5 Billion Facility
Line of Credit Facility
Line of credit facility, maximum borrowing capacity				$ 2,500,000,000.0			$ 2,500,000,000.0
Amount of borrowings				500,000,000	$ 0		500,000,000	$ 0			1,300,000,000
Letters of credit outstanding under revolving credit facility				0	0		0	0			159,400,000
Maximum amount of outstanding short-term loans at any time during the period				700,000,000	$ 0		1,600,000,000	$ 0
Average daily balance of short-term loans outstanding during the period				$ 300,000,000			$ 900,000,000
Weighted average interest rates of average daily balance of short-term loans				3.60%			3.30%
Revolving credit facility \| RMP $850 Million Facility
Line of Credit Facility
Amount of borrowings											286,000,000
Letters of credit outstanding under revolving credit facility											$ 1,000,000
Maximum amount of outstanding short-term loans at any time during the period		$ 260,000,000				$ 375,000,000
Average daily balance of short-term loans outstanding during the period				$ 249,000,000			$ 300,000,000
Weighted average interest rates of average daily balance of short-term loans				4.10%			3.80%
EQM Term Loan Facility \| EQM
Line of Credit Facility
Line of credit facility, maximum borrowing capacity										$ 2,500,000,000.0
Maximum amount of outstanding short-term loans at any time during the period			$ 1,825,000,000
Average daily balance of short-term loans outstanding during the period			$ 1,231,000,000
Write off of deferred debt issuance cost							$ 3,000,000
Weighted average interest rate			3.30%