Midstream (EQTNP) 10-Q 30 Jul 19 2019 Q2 Quarterly report Financial data

Cover

Cover shares in Thousands	6 Months Ended
	Jun. 30, 2019shares
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	001-38629
Entity Registrant Name	EQUITRANS MIDSTREAM CORPORATION
Entity Incorporation, State or Country Code	PA
Entity Tax Identification Number	83-0516635
Entity Address, Address Line One	625 Liberty Avenue, Suite 2000
Entity Address, City or Town	Pittsburgh
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15222
City Area Code	412
Local Phone Number	395-2688
Title of 12(b) Security	Common Stock
Trading Symbol	ETRN
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Emerging Growth Company	false
Entity Filer Category	Non-accelerated Filer
Small Business Entity	false
Entity Shell Company	false
Entity Common Units, Unit Outstanding	254,691
Entity Central Index Key	0001747009
Amendment Flag	false
Current Fiscal Year End	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2

Statements of Condensed Consoli

Statements of Condensed Consolidated Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Income Statement [Abstract]
Operating revenues	[1]	$ 406,167	$ 374,697	$ 795,949		$ 745,723
Operating expenses:
Operating and maintenance	[2]	46,556	43,270	74,439		70,442
Selling, general and administrative	[2]	27,224	28,260	59,402		55,473
Separation and other transaction costs	[2]	15,568	15,741	24,350		31,314
Depreciation		56,759	42,171	107,270		83,513
Amortization of intangible assets		13,750	10,387	24,137		20,773
Impairment of long-lived assets	[3]	80,135	0	80,135	[4]	0	[4]
Total operating expenses		239,992	139,829	369,733		261,515
Operating income		166,175	234,868	426,216		484,208
Equity income	[5]	36,782	10,938	67,845		19,749
Other income		706	944	2,567		1,848
Net interest expense	[6]	61,713	19,884	122,662		31,986
Income before income taxes		141,950	226,866	373,966		473,819
Income tax expense		11,470	7,259	43,920		30,468
Net income		130,480	219,607	330,046		443,351
Net income attributable to noncontrolling interests		55,959	118,540	199,226		259,555
Net income attributable to Equitrans Midstream		$ 74,521	$ 101,067	$ 130,820		$ 183,796
Basic:
Weighted average common stock outstanding (in shares)		254,917	254,432	254,845		254,432
Net income (in dollars per share)		$ 0.29	$ 0.40	$ 0.51		$ 0.72
Diluted:
Weighted average common stock outstanding (in shares)		254,967	255,033	254,895		255,033
Net income (in dollars per share)		$ 0.29	$ 0.40	$ 0.51		$ 0.72
Net income		$ 130,480	$ 219,607	$ 330,046		$ 443,351
Other comprehensive income (loss), net of tax:
2019 Pension and other post-retirement benefits liability adjustment, net of tax expense of $7 and $15		22	0	(273)		0
Other comprehensive income (loss)		22	0	(273)		0
Comprehensive income		130,502	219,607	329,773		443,351
Less: Comprehensive income attributable to noncontrolling interests		55,959	118,540	199,226		259,555
Comprehensive income attributable to Equitrans Midstream		$ 74,543	$ 101,067	$ 130,547		$ 183,796
Dividends declared per common share (in dollars per share)		$ 0.45	$ 0	$ 0.90		$ 0
[1]	Operating revenues included related party revenues from EQT Corporation (NYSE: EQT) of $284.0 million and $285.3 million for the three months ended June 30, 2019 and 2018 , respectively, and $568.5 million and $550.9 million for the six months ended June 30, 2019 and 2018 , respectively. See Note 8 .
[2]	Operating and maintenance expense charges to EQT of $2.4 million for both the three and six months ended June 30, 2019 . For the three and six months ended June 30, 2018 , operating and maintenance expense included charges from EQT of $12.2 million and $24.4 million , respectively. Selling, general and administrative expense included charges from EQT of $1.0 million for both the three and six months ended June 30, 2019 . Selling, general and administrative expense included charges from EQT of $26.1 million and $50.7 million for the three and six months ended June 30, 2018 , respectively. See Note 8 . Separation and other transaction costs for the three and six months ended June 30, 2018 represents the expenses related to the Rice Merger, the EQM-RMP Mergers and the Drop-Down Transaction (each defined in Note 1 ) and included charges allocated to Equitrans Midstream from EQT of $10.4 million and $26.0 million , respectively. See Notes 1 and 8 .
[3]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.
[4]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.
[5]	Represents equity income from Mountain Valley Pipeline, LLC (the MVP Joint Venture). See Note 9 .
[6]	Net interest expense included interest income on the preferred interest in EQT Energy Supply, LLC (EES) (Preferred Interest) of $1.6 million and $1.7 million for the three months ended June 30, 2019 and 2018 , respectively, and $3.2 million and $3.3 million for the six months ended June 30, 2019 and 2018 , respectively.

Statements of Condensed Conso_2

Statements of Condensed Consolidated Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Pension and other post-retirement benefits liability adjustment, tax expense		$ 7	$ 0	$ 15	$ 0
Operating and maintenance expense	[1]	46,556	43,270	74,439	70,442
Selling, general and administrative expense	[1]	27,224	28,260	59,402	55,473
Transaction costs	[1]	15,568	15,741	24,350	31,314
EQT Corporation and Subsidiaries
Affiliated revenues		284,000	285,300	568,500	550,900
Operating and maintenance expense		2,400	12,200	2,400	24,400
Selling, general and administrative expense		1,000	26,100	1,000	50,700
Transaction costs			10,400		26,000
EES
Interest income		$ 1,600	$ 1,700	$ 3,200	$ 3,300
[1]	Operating and maintenance expense charges to EQT of $2.4 million for both the three and six months ended June 30, 2019 . For the three and six months ended June 30, 2018 , operating and maintenance expense included charges from EQT of $12.2 million and $24.4 million , respectively. Selling, general and administrative expense included charges from EQT of $1.0 million for both the three and six months ended June 30, 2019 . Selling, general and administrative expense included charges from EQT of $26.1 million and $50.7 million for the three and six months ended June 30, 2018 , respectively. See Note 8 . Separation and other transaction costs for the three and six months ended June 30, 2018 represents the expenses related to the Rice Merger, the EQM-RMP Mergers and the Drop-Down Transaction (each defined in Note 1 ) and included charges allocated to Equitrans Midstream from EQT of $10.4 million and $26.0 million , respectively. See Notes 1 and 8 .

Statements of Condensed Conso_3

Statements of Condensed Consolidated Cash Flows (Unaudited) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income		$ 330,046	$ 443,351
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation		107,270	83,513
Amortization of intangible assets		24,137	20,773
Deferred income taxes		43,920	(164,039)
Impairment of long-lived assets	[1],[2]	80,135	0
Equity income	[3]	(67,845)	(19,749)
Other income		(2,851)	(2,137)
Non-cash long-term compensation expense		2,618	808
Changes in other assets and liabilities:
Accounts receivable		(12,094)	(26,449)
Accounts payable		(48,907)	78,463
Accrued interest		(6,608)	2,220
Other assets and other liabilities		(27,278)	32,887
Net cash provided by operating activities		422,543	449,641
Cash flows from investing activities:
Capital expenditures		(482,578)	(382,946)
Capital contributions to the MVP Joint Venture		(301,175)	(182,805)
Bolt-on Acquisition (defined in Note 3), net of cash acquired		(848,625)	0
Principal payments received on the Preferred Interest		2,298	2,172
Net cash used in investing activities		(1,630,080)	(563,579)
Cash flows from financing activities:
Proceeds from credit facility borrowings		1,129,000	2,390,500
Payments on credit facility borrowings		(670,500)	(2,596,500)
Proceeds from the issuance of EQM's long-term debt		0	2,500,000
Net payments on EQGP's Working Capital Facility loan		0	(141)
Cash paid for long-term debt		(31,325)	0
Net distributions to EQT		0	(67,454)
Proceeds from issuance of Series A Preferred Units, net of offering costs		1,158,313	0
Distributions paid to noncontrolling interest unitholders		189,308	180,745
Acquisition of 25% of Strike Force Midstream LLC		0	175,000
Debt discount, debt issuance costs and credit facility origination fees		0	(30,295)
Dividends paid		(218,859)	0
Purchase of EQGP common units		238,455	0
Net cash provided by financing activities		938,866	1,840,365
Net change in cash and cash equivalents		(268,671)	1,726,427
Cash and cash equivalents at beginning of period		294,172	121,004
Cash, restricted cash and cash equivalents at end of period		25,501	1,847,431
Cash paid during the period for:
Interest, net of amount capitalized		127,542	33,573
Non-cash activity during the period for:
Settlement of transaction costs with EQT		0	87,982
Net settlement of current income taxes payable with EQT		$ 0	$ 54,033
[1]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.
[2]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.
[3]	Represents equity income from Mountain Valley Pipeline, LLC (the MVP Joint Venture). See Note 9 .

Statements of Condensed Conso_4

Statements of Condensed Consolidated Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Statement of Cash Flows [Abstract]
Distributions paid to noncontrolling interest unitholders	$ (189,308)	$ (180,745)
Percentage of voting interests acquired		25.00%

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents		$ 25,501	$ 294,172
Accounts receivable (net of allowance for doubtful accounts of $138 and $75 as of June 30, 2019 and December 31, 2018, respectively)	[1]	282,805	255,496
Other current assets		24,968	19,171
Total current assets		333,274	568,839
Property, plant and equipment		8,165,435	6,469,846
Less: accumulated depreciation		(785,176)	(602,199)
Net property, plant and equipment		7,380,259	5,867,647
Investment in unconsolidated entity		2,066,330	1,510,289
Goodwill		1,347,138	1,239,269
Net intangible assets		868,965	576,113
Deferred income taxes		203,479	597,321
Other assets		237,008	164,357
Total assets		12,436,453	10,523,835
Current liabilities:
Current portion of long-term debt		6,000	6,000
Accounts payable	[2]	181,077	210,007
Capital contribution payable to the MVP Joint Venture		356,223	169,202
Accrued interest		73,753	80,236
Accrued liabilities		76,847	84,011
Total current liabilities		693,900	549,456
Credit facility borrowings		1,372,500	641,500
EQM senior notes		3,459,323	3,456,639
Long-term debt		562,295	562,105
Regulatory and other long-term liabilities		103,258	54,502
Total liabilities		6,191,276	5,264,202
Equity:
Common stock, no par value, 254,691 and 254,271 units issued and outstanding as of June 30, 2019 and December 31, 2018, respectively		1,381,810	425,370
Retained (deficit) earnings		(53,791)	33,932
Accumulated other comprehensive loss		(1,782)	(1,509)
Total common shareholders' equity		1,326,237	457,793
Noncontrolling interests		4,918,940	4,801,840
Total shareholders' equity		6,245,177	5,259,633
Total liabilities and shareholders' equity		$ 12,436,453	$ 10,523,835
[1]	Accounts receivable as of June 30, 2019 and December 31, 2018 included approximately $126.7 million and $175.9 million , respectively, of accounts receivable due from EQT.
[2]	Accounts payable as of December 31, 2018 included approximately $34.1 million due to EQT. There was no related party balance with EQT included in accounts payable as of June 30, 2019 .

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Accounts receivable, for doubtful accounts	$ 138	$ 75
Accounts receivable, related parties	126,700	175,900
Accounts payable, related parties	$ 0	$ 34,100
Common stock, shares issued (in shares)	254,691	254,271
Common stock, shares outstanding (in shares)	254,691	254,271

Statements of Condensed Conso_5

Statements of Condensed Consolidated Equity (Unaudited) - USD ($) shares in Thousands	Total	Parent Net Investment	Common Stock	Retained Earnings (Deficit)	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Beginning balance at Dec. 31, 2017	$ 6,238,764,000	$ 1,143,769,000	$ 0	$ 0	$ 0	$ 5,094,995,000
Beginning balance (in shares) at Dec. 31, 2017			0
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	223,744,000	82,729,000				141,015,000
Net contributions from EQT	92,074,000	92,074,000
Share-based compensation plans, net	707,000	317,000				390,000
Distributions paid to noncontrolling interest unitholders	(88,896,000)					(88,896,000)
Net changes in ownership of consolidated entities	(17,000)	47,000				(64,000)
Ending balance at Mar. 31, 2018	6,466,376,000	1,318,936,000	$ 0	0	0	5,147,440,000
Ending balance (in shares) at Mar. 31, 2018			0
Beginning balance at Dec. 31, 2017	6,238,764,000	1,143,769,000	$ 0	0	0	5,094,995,000
Beginning balance (in shares) at Dec. 31, 2017			0
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	443,351,000
Ending balance at Jun. 30, 2018	6,408,593,000	1,385,257,000	$ 0	0	0	5,023,336,000
Ending balance (in shares) at Jun. 30, 2018			0
Beginning balance at Dec. 31, 2017	6,238,764,000	1,143,769,000	$ 0	0	0	5,094,995,000
Beginning balance (in shares) at Dec. 31, 2017			0
Increase (Decrease) in Partners' Capital [Roll Forward]
Purchase of EQGP common units			$ 46,800,000
Ending balance at Dec. 31, 2018	$ 5,259,633,000	0	$ 425,370,000	33,932,000	(1,509,000)	4,801,840,000
Ending balance (in shares) at Dec. 31, 2018	254,271		254,271
Beginning balance at Mar. 31, 2018	$ 6,466,376,000	1,318,936,000	$ 0	0	0	5,147,440,000
Beginning balance (in shares) at Mar. 31, 2018			0
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	219,607,000	101,067,000				118,540,000
Net contributions from EQT	(17,513,000)	(17,513,000)
Share-based compensation plans, net	101,000					101,000
Distributions paid to noncontrolling interest unitholders	(91,849,000)					(91,849,000)
Purchase of Strike Force Midstream LLC noncontrolling interests	(175,000,000)	1,818,000				(176,818,000)
Net changes in ownership of consolidated entities	6,871,000	(19,051,000)				25,922,000
Ending balance at Jun. 30, 2018	6,408,593,000	1,385,257,000	$ 0	0	0	5,023,336,000
Ending balance (in shares) at Jun. 30, 2018			0
Beginning balance at Dec. 31, 2018	$ 5,259,633,000	0	$ 425,370,000	33,932,000	(1,509,000)	4,801,840,000
Beginning balance (in shares) at Dec. 31, 2018	254,271		254,271
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	$ 199,566,000			56,299,000		143,267,000
Pension and other post-retirement benefits liability adjustment, net of tax expense	21,000			316,000	(295,000)
Dividends	(104,251,000)			(104,251,000)
Share-based compensation plans, net (in shares)			413
Share-based compensation plans, net	1,108,000		$ 853,000			255,000
Distributions paid to noncontrolling interest unitholders	(94,030,000)					(94,030,000)
Purchase of EQGP common units	(238,455,000)		(38,648,000)			(199,807,000)
Net changes in ownership of consolidated entities	(346,543,000)		991,098,000			(1,337,641,000)
Ending balance at Mar. 31, 2019	4,677,049,000	0	$ 1,378,673,000	(13,704,000)	(1,804,000)	3,313,884,000
Ending balance (in shares) at Mar. 31, 2019			254,684
Beginning balance at Dec. 31, 2018	$ 5,259,633,000	0	$ 425,370,000	33,932,000	(1,509,000)	4,801,840,000
Beginning balance (in shares) at Dec. 31, 2018	254,271		254,271
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	$ 330,046,000
Net changes in ownership of consolidated entities	346,500,000		$ 991,100,000			1,300,000,000
Ending balance at Jun. 30, 2019	$ 6,245,177,000	0	$ 1,381,810,000	(53,791,000)	(1,782,000)	4,918,940,000
Ending balance (in shares) at Jun. 30, 2019	254,691		254,691
Beginning balance at Mar. 31, 2019	$ 4,677,049,000	0	$ 1,378,673,000	(13,704,000)	(1,804,000)	3,313,884,000
Beginning balance (in shares) at Mar. 31, 2019			254,684
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	130,480,000			74,521,000		55,959,000
Pension and other post-retirement benefits liability adjustment, net of tax expense	22,000			0	22,000
Dividends	(114,608,000)			(114,608,000)
Share-based compensation plans, net (in shares)			7
Share-based compensation plans, net	1,510,000		$ 1,510,000			0
Distributions paid to noncontrolling interest unitholders	(95,278,000)					(95,278,000)
Issuance of Series A Preferred Units, net of offering costs	1,158,313,000					1,158,313,000
Bolt-on Acquisition (Note 3)	486,062,000					486,062,000
Net changes in ownership of consolidated entities	1,627,000		1,627,000
Ending balance at Jun. 30, 2019	$ 6,245,177,000	$ 0	$ 1,381,810,000	$ (53,791,000)	$ (1,782,000)	$ 4,918,940,000
Ending balance (in shares) at Jun. 30, 2019	254,691		254,691

Statements of Condensed Conso_6

Statements of Condensed Consolidated Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2018
Dividends (in dollars per share)	$ 0.45	$ 0.41
Pension and other post-retirement benefits liability adjustment, tax expense	$ 7	$ 8
EQM Midstream Partners, LP
Cash distributions paid per unit (in dollars per share)	$ 1.145	$ 1.13	$ 1.025
EQGP Holdings, LP
Cash distributions paid per unit (in dollars per share)			0.244
Rice Midstream Partners, LP
Cash distributions paid per unit (in dollars per share)			$ 0.2917

Financial Statements

Financial Statements	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Statements	Financial Statements Organization. On November 12, 2018, Equitrans Midstream, EQT and, for certain limited purposes, EQT Production Company, a wholly-owned subsidiary of EQT, entered into a separation and distribution agreement (the Separation and Distribution Agreement), pursuant to which, among other things, EQT effected the Separation, including the transfer of certain assets and liabilities to Equitrans Midstream, and distributed 80.1% of the then outstanding shares of common stock, no par value, of Equitrans Midstream (Equitrans Midstream common stock) to EQT shareholders of record as of the close of business on November 1, 2018 (the Distribution). The Distribution was effective at 11:59 p.m., Eastern Time, on November 12, 2018 (the Separation Date). EQT retained the remaining 19.9% of the outstanding shares in Equitrans Midstream (the Retained Interest). Immediately following the Separation, the Company held investments in the entities then-conducting the Midstream Business, including limited and general partner interests in EQGP Holdings, LP (formerly known as EQT GP Holdings, LP) (EQGP), which, as of December 31, 2018, owned limited partner interests, the entire general partner interest and all of the incentive distribution rights (IDRs) in EQM Midstream Partners, LP (formerly known as EQT Midstream Partners, LP) (NYSE: EQM) (EQM). As of December 31, 2018, the common units representing limited partner interests in EQGP were owned by Equitrans Gathering Holdings, LLC (formerly known as EQT Gathering Holdings, LLC) (Equitrans Gathering Holdings), EQM GP Corporation (EQM GP Corp) and Equitrans Midstream Holdings, LLC (EMH). Following the closing of the EQGP Unit Purchases and the exercise of the Limited Call Right (each defined and discussed in Note 2 and collectively referred to as the EQGP Buyout), EQGP became an indirect, wholly-owned subsidiary of Equitrans Midstream. EQM owns, operates, acquires and develops midstream assets in the Appalachian Basin. As of December 31, 2018, EQM Midstream Services, LLC (formerly known as EQT Midstream Services, LLC) (the Former EQM General Partner) was a wholly-owned subsidiary of EQGP and EQM's general partner. As of December 31, 2018, EQGP Services, LLC (formerly known as EQT GP Services, LLC) (the Former EQGP General Partner or New EQM General Partner) was a wholly-owned subsidiary of Equitrans Gathering Holdings and EQGP's general partner. Equitrans Midstream's assets, liabilities and results of operations also include the legacy assets of Rice Midstream Holdings LLC (Rice Midstream Holdings). EQT obtained control of Rice Midstream Holdings on November 13, 2017 (the Rice Merger Date), when, pursuant to the agreement and plan of merger dated June 19, 2017 by and among EQT, Rice Energy Inc. (Rice Energy) and a wholly-owned subsidiary of EQT, Rice Energy became a wholly-owned, indirect subsidiary of EQT, and EQT became the indirect parent of Rice Midstream Holdings (the Rice Merger). The operations of Rice Midstream Holdings were primarily conducted through Rice Midstream Partners LP (now known as RM Partners LP) (RMP), Rice West Virginia Midstream LLC (now known as EQM West Virginia Midstream LLC) (EQM West Virginia), Rice Olympus Midstream LLC (now known as EQM Olympus Midstream LLC) (EQM Olympus) and Strike Force Midstream Holdings LLC (Strike Force Holdings). At the Rice Merger Date, Strike Force Holdings owned 75% of the outstanding limited liability company interests in Strike Force Midstream LLC (Strike Force Midstream), a Delaware limited liability company. Rice Midstream Holdings, through its wholly-owned, indirect subsidiary Rice Midstream GP Holdings LP (RMGP), owned Rice Midstream Management LLC (now known as EQM Midstream Management LLC), RMP's general partner (the RMP General Partner), as well as limited partner interests and all of the IDRs in RMP. Rice Midstream Holdings controlled the RMP General Partner and therefore consolidated the results of RMP. In 2018, EQM obtained control of the operating entities of Rice Midstream Holdings through the following transactions: • On April 25, 2018, EQM, RMP and certain of their affiliates entered into an agreement and plan of merger, pursuant to which EQM acquired RMP and the RMP General Partner (the EQM-RMP Mergers). The EQM-RMP Mergers closed on July 23, 2018. • On May 1, 2018, EQM acquired the remaining outstanding limited liability company interests in Strike Force Midstream from Gulfport Midstream Holdings, LLC (Gulfport Midstream), an affiliate of Gulfport Energy Corporation, in exchange for $175 million in cash (the Gulfport Transaction). As a result, EQM owned 100% of Strike Force Midstream. • On May 22, 2018, and effective May 1, 2018, EQM, through its wholly-owned subsidiary EQM Gathering Holdings, LLC, a Delaware limited liability company (EQM Gathering), acquired all the outstanding limited liability company interests in each of EQM West Virginia, EQM Olympus and Strike Force Holdings (collectively the Drop-Down Entities), pursuant to the terms of a contribution and sale agreement dated as of April 25, 2018 by and among EQM, EQM Gathering, EQT and Rice Midstream Holdings, in exchange for an aggregate of 5,889,282 common units representing limited partner interests in EQM (EQM common units) and cash consideration of $1.15 billion , plus working capital adjustments (the Drop-Down Transaction). As a result of the closing of the Drop-Down Transaction, effective May 1, 2018, the Drop-Down Entities and Strike Force Midstream became indirect, wholly-owned subsidiaries of EQM. Basis of Presentation. As of December 31, 2018, the Former EQGP General Partner was a wholly-owned subsidiary of Equitrans Gathering and controlled EQGP through its general partner interest in EQGP; therefore, the financial statements of Equitrans Midstream consolidated and, following the closing of the EQGP Unit Purchases and the exercise of the Limited Call Right, continue to consolidate EQGP. As of December 31, 2018, the Former EQM General Partner was a wholly-owned subsidiary of EQGP and controlled EQM through its general partner interest in EQM; therefore, the financial statements of EQGP consolidated EQM. For each of the periods prior to the Separation presented in this Quarterly Report on Form 10-Q, the consolidated financial statements and related notes include the assets, liabilities and results of operations of the Midstream Business that were transferred to Equitrans Midstream upon the closing of the Distribution and represent the predecessor for accounting purposes of Equitrans Midstream (the Predecessor). References in these financial statements to Equitrans Midstream or the Company refer collectively to Equitrans Midstream Corporation and the Predecessor as applicable for all periods presented. Predecessor financial information has been derived from EQT's consolidated financial statements and accounting records and reflects the historical results of operations, financial position and cash flows of the Company as if the Midstream Business had been consolidated for all periods presented. The financial statements include expense allocations for certain corporate functions historically performed by EQT, such as executive oversight, accounting, treasury, tax, legal, supply chain, information technology and share-based compensation. See Note 8 . The Company believes the assumptions underlying the consolidated financial statements are reasonable; however, as organizational structure and strategic focus dictate expenses incurred, the financial statements may not include all expenses that would have been incurred had the Company existed as a standalone, publicly traded company for the six months ended June 30, 2018 . Similarly, the financial statements may not reflect the results of operations, financial position and cash flows had the Company existed as a standalone, publicly traded company during that period. Following the completion of the Bolt-on Acquisition, the Company, through EQM, evaluated Eureka Midstream Holdings, LLC (Eureka Midstream) for consolidation and determined that Eureka Midstream does not meet the criteria for variable interest entity classification due to its ability to independently finance its operations through the Eureka Credit Facility (as defined in Note 10 ), as well as each member having proportional voting rights through their equity investments. As such, as of June 30, 2019 , EQM consolidates Eureka Midstream using the voting interest model, recording noncontrolling interest related to the third-party ownership interests in Eureka Midstream. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the requirements of Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, these unaudited condensed consolidated financial statements include all adjustments (consisting of only normal, recurring adjustments, unless otherwise disclosed in this Form 10-Q) necessary for a fair presentation of the financial position of the Company as of June 30, 2019 and December 31, 2018 , the results of its operations and its equity for the three and six months ended June 30, 2019 and 2018 and its cash flows for the six months ended June 30, 2019 and 2018 . The condensed consolidated balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and notes required by GAAP for complete financial statements. Due to the seasonal nature of EQM's utility customer contracts, the interim statements for the three and six months ended June 30, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 . For further information, refer to the Company's annual combined consolidated financial statements and related notes for the year ended December 31, 2018 , as well as "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained therein. Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases . The standard requires entities to record assets and obligations for contracts currently recognized as operating leases. In July 2018, the FASB issued ASU 2018-11, Leases (Topic 842): Targeted Improvements . The update provides an optional transition method of adoption that permits entities to initially apply the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Under the optional transition method, comparative financial information and disclosures are not required. The update also provides transition practical expedients. The standard requires disclosures of the nature, maturity and value of an entity's lease liabilities and elections taken by the entity. In March 2019, the FASB issued ASU 2019-01, Leases (Topic 842): Codification Improvements , which, among other things, clarifies interim disclosure requirements in the year of ASU 2016-02 adoption. The Company adopted ASU 2016-02, ASU 2018-11 and ASU 2019-01 on January 1, 2019 using the optional transition method. The Company uses a lease accounting system to monitor its current population of lease contracts. The Company implemented processes and controls to review new lease contracts for appropriate accounting treatment in the context of the standards and to generate disclosures required under the standards. For the disclosures required by the standards, see Note 5 . In June 2016, the FASB issued ASU 2016-13, Financial Instruments — Credit Losses: Measurement of Credit Losses on Financial Instruments . The standard amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this standard eliminates the probable initial recognition threshold in current GAAP and, in its place, requires an entity to recognize its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposures, reinsurance receivables and any other financial assets not excluded from the scope of the standard that have the contractual right to receive cash. The standard will be effective for annual reporting periods beginning after December 15, 2019, including interim periods within that reporting period. The Company is currently evaluating the effect this standard will have on its financial statements and related disclosures. In February 2018, the FASB issued ASU 2018-02, Income Statement, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which allows for a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act and will improve the usefulness of information reported to financial statement users. The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company adopted the standard in the first quarter of 2019 with no significant effect on its financial statements or related disclosures. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement, Changes to the Disclosure Requirements for Fair Value Measurement , which makes a number of changes to the hierarchy associated with Level 1, 2 and 3 fair value measurements and the related disclosure requirements. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. The Company is currently evaluating the effect this standard will have on its financial statements and related disclosures but does not expect the adoption of this standard to have a material effect on its financial statements and related disclosures. In August 2018, the FASB issued ASU 2018-15, Intangibles—Goodwill and Other: Internal-Use Software , which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company early-adopted the standard using the prospective method of adoption on January 1, 2019. Following the adoption of ASU 2018-15, the Company began capitalizing certain implementation costs related to cloud computing arrangements that are service contracts. The capitalized portion of these costs are included in the property, plant and equipment line on the consolidated balance sheets and will be amortized over the term of the Company's hosting arrangement, which has a fixed term of seven years . For the three and six months ended June 30, 2019 , the Company did no t recognize any amortization expense related to implementation costs on its cloud computing arrangements as such assets were not in use. The costs will be included in the selling, general and administrative expense line on the accompanying statements of consolidated comprehensive income when recognized. In August 2018, the U.S. Securities and Exchange Commission (SEC) adopted a final rule under SEC Release No. 33-10532, Disclosure Update and Simplification , that amends certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. The amendments also expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements, in that registrants must now analyze changes in stockholders’ equity, in the form of reconciliation, for the current and comparative year-to-date periods, with subtotals for each interim period. This final rule was effective on November 5, 2018 and the Company assessed the impact on its consolidated financial statements disclosures to be not significant. The Company adopted the final rule and began applying this disclosure change to its statement of condensed consolidated equity in the first quarter of 2019.

Investments in Consolidated, No

Investments in Consolidated, Non-Wholly-Owed Entities	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Investments in Consolidated, Non-Wholly-Owed Entities	Investments in Consolidated, Non-Wholly-Owned Entities Investment in EQGP EQGP Unit Purchases . On December 31, 2018, the Company closed on the acquisition of an aggregate 14,560,281 EQGP common units pursuant to certain Unit Purchase Agreements with funds managed by Neuberger Berman Investment Adviser LP, funds managed by Goldman Sachs Asset Management, L.P., funds managed by Cushing Asset Management, LP, funds managed by Kayne Anderson Capital Advisors, L.P., and ZP Energy Fund, L.P. (the Initial Unit Purchase Closing) for an aggregate purchase price of $291.2 million . The Initial Unit Purchase Closing resulted in a reduction of additional paid-in capital of $46.8 million and a decrease in noncontrolling interest in consolidated subsidiaries of $244.4 million for the year ended December 31, 2018. On January 2, 2019 and January 3, 2019, the Company closed on the acquisition of the remaining 804,140 EQGP common units purchased pursuant to the Unit Purchase Agreements for an aggregate purchase price of $16.1 million (together with the Initial Unit Purchase Closing on December 31, 2018 , the EQGP Unit Purchases). Limited Call Right. Following the Initial Unit Purchase Closing, on December 31, 2018 , the Company exercised a limited call right (the Limited Call Right), under EQGP's partnership agreement, pursuant to which, on January 10, 2019, the Company closed on the acquisition of the remaining 11,097,287 outstanding EQGP common units not owned by the Company or its affiliates for an aggregate purchase price of $221.9 million (such acquisition, together with the EQGP Unit Purchases, the EQGP Buyout), and EQGP became an indirect, wholly-owned subsidiary of the Company. In connection with the completion of the EQGP Buyout on January 10, 2019, certain non-employee members of the Board of Directors of the Former EQGP General Partner stepped down from their roles and were paid $20.00 for each EQGP phantom unit that they held, which was, in the aggregate, 29,829 EQGP phantom units, including accrued distributions. Termination of the EQGP Omnibus Agreement and EQGP Working Capital Facility. On January 10, 2019, in connection with the completion of the EQGP Buyout, EQGP's omnibus agreement with Equitrans Midstream and certain other parties and the EQGP Working Capital Facility (as defined in Note 8 ) with the Company were terminated. In connection with the termination of the EQGP Working Capital Facility, the Company agreed that all loans and other amounts outstanding and all other obligations of EQGP to the Company under the EQGP Working Capital Facility were deemed forgiven, satisfied, discharged and paid in full. Investment in EQM EQM IDR Transaction . On February 22, 2019, Equitrans Midstream completed its previously announced simplification transaction pursuant to that certain Agreement and Plan of Merger, dated as of February 13, 2019 (the IDR Merger Agreement) by and among Equitrans Midstream and certain related parties, pursuant to which, among other things, (i) Equitrans Merger Sub, LP, a party to the IDR Merger Agreement, merged with and into EQGP (the Merger) with EQGP continuing as the surviving limited partnership and a wholly owned subsidiary of EQM following the Merger, and (ii) each of (a) the IDRs, (b) the economic portion of the general partner interest in EQM and (c) the issued and outstanding EQGP common units were canceled, and, as consideration for such cancellation, certain affiliates of the Company received on a pro rata basis 80,000,000 newly-issued EQM common units and 7,000,000 newly-issued Class B units (Class B units), both representing limited partner interests in EQM, and EQGP Services, LLC retained the non-economic general partner interest in EQM (the EQM IDR Transaction). Additionally, as part of the EQM IDR Transaction, the 21,811,643 EQM common units held by EQGP were canceled and 21,811,643 EQM common units were issued pro rata to certain affiliates of Equitrans Midstream. As a result of the EQM IDR Transaction, EQGP Services, LLC replaced EQM Midstream Services, LLC as the general partner of EQM (the New EQM General Partner). The Class B units are substantially similar in all respects to EQM common units, except that the Class B units are not entitled to receive distributions of available cash until the applicable Class B unit conversion date (or, if earlier, a change of control). The Class B units are divided into three tranches, with the first tranche of 2,500,000 Class B units becoming convertible at the holder's option into EQM common units on April 1, 2021, the second tranche of 2,500,000 Class B units becoming convertible at the holder's option into EQM common units on April 1, 2022 and the third tranche of 2,000,000 Class B units becoming convertible at the holder's option into EQM common units on April 1, 2023 (each, a Class B unit conversion date). Additionally, the Class B units will become convertible at the holder's option into EQM common units immediately before a change of control of EQM. After the applicable Class B unit conversion date (or, if earlier, a change of control), whether or not such Class B units have been converted into EQM common units, the Class B units will participate pro rata with the EQM common units in distributions of available cash. The holders of Class B units vote together with the holders of EQM common units as a single class, except that Class B units owned by the general partner of EQM and its affiliates are excluded from voting if EQM common units owned by such parties are excluded from voting. Holders of Class B units are entitled to vote as a separate class on any matter that adversely affects the rights or preferences of the Class B units in relation to other classes of EQM partnership interests in any material respect or as required by law. After giving effect to the EQM IDR Transaction, including the issuance of Class B units, Equitrans Gathering Holdings, EQM GP Corp and EMH, each a wholly-owned subsidiary of Equitrans Midstream, held 89,505,616 , 89,536 and 27,650,303 EQM common units, respectively. Additionally, Equitrans Gathering Holdings, EQM GP Corp and EMH held 6,153,907 , 6,155 and 839,938 EQM Class B units, respectively. As of June 30, 2019 , the Company owned, directly or indirectly 117,245,455 EQM common units and 7,000,000 Class B units (which, after taking into account the Series A Preferred Units (as defined below) issued in the Private Placement (as defined below) on an as-converted basis, collectively represented a 53.5% limited partner interest in EQM) and the entire non-economic general partner interest in EQM, while the public owned a 46.5% limited partner interest in EQM. Following the completion of the Private Placement, certain investors owned an aggregate of 24,605,291 Series A Preferred Units. During the first quarter of 2019, as a result of the EQM IDR Transaction, the Company recorded, in the aggregate, a $991.1 million increase of common stock, no par value, a decrease in noncontrolling interest of $1.3 billion and a decrease in deferred tax asset of $346.5 million . EQM Series A Preferred Units. On March 13 , 2019, EQM entered into a Convertible Preferred Unit Purchase Agreement (inclusive of certain Joinder Agreements entered into on March 18, 2019, the Preferred Unit Purchase Agreement) with certain investors to issue and sell in a private placement (the Private Placement) an aggregate of 24,605,291 Series A Perpetual Convertible Preferred Units (Series A Preferred Units) representing limited partner interests in EQM for a cash purchase price of $48.77 per Series A Preferred Unit, resulting in total gross proceeds of approximately $1.2 billion . The net proceeds from the Private Placement were used in part to fund the purchase price in the Bolt-on Acquisition (defined in Note 3 ) and to pay certain fees and expenses related to the Bolt-on Acquisition, and the remainder was used for general partnership purposes. The Private Placement closed concurrently with the closing of the Bolt-on Acquisition on April 10, 2019 . See Note 3 . The Series A Preferred Units rank senior to all common units and Class B units representing limited partner interests in EQM with respect to distribution rights and rights upon liquidation. The Series A Preferred Units will vote on an as-converted basis with the EQM common units and Class B units and will have certain other class voting rights with respect to any amendment to EQM's partnership agreement or its certificate of limited partnership that would be adverse (other than in a de minimis manner) to any of the rights, preferences or privileges of the Series A Preferred Units. The holders of the Series A Preferred Units are entitled to receive cumulative quarterly distributions at a rate of $1.0364 per Series A Preferred Unit for the first twenty distribution periods, and thereafter the quarterly distributions on the Series A Preferred Units will be an amount per Series A Preferred Unit for such quarter equal to (i) the Series A Preferred Unit purchase price of $48.77 per such unit, multiplied by (ii) a percentage equal to the sum of (A) the greater of (x) the 3-month LIBOR as of the second London banking day prior to the beginning of the applicable quarter and (y) 2.59% , and (B) 6.90%, multiplied by (iii) 25%. EQM will not be entitled to pay any distributions on any junior securities, including any EQM common units, prior to paying the quarterly distributions payable to the holders of Series A Preferred Units, including any previously accrued and unpaid distributions. Each holder of the Series A Preferred Units may elect to convert all or any portion of the Series A Preferred Units owned by it into EQM common units initially on a one-for-one basis, subject to customary anti-dilution adjustments and an adjustment for any distributions that have accrued but have not been paid when due and partial period distributions, at any time (but not more often than once per fiscal quarter) after April 10, 2021 (or earlier liquidation, dissolution or winding up of EQM), provided that any conversion is for at least $30 million (calculated based on the closing price of the EQM common units on the trading day preceding notice of conversion) or such lesser amount if such conversion relates to all of a holder’s remaining Series A Preferred Units. EQM may elect to convert all or any portion of the Series A Preferred Units into EQM common units at any time (but not more often than once per quarter) after April 10, 2021 if (i) the common units are listed for, or admitted to, trading on a national securities exchange, (ii) the closing price per common unit on the national securities exchange on which the common units are listed for, or admitted to, trading exceeds 140% of the Series A Preferred Unit purchase price of $48.77 per such unit for the 20 consecutive trading days immediately preceding notice of the conversion, (iii) the average daily trading volume of the common units on the national securities exchange on which the common units are listed for, or admitted to, trading exceeds 500,000 common units for the 20 consecutive trading days immediately preceding notice of the conversion, (iv) EQM has an effective registration statement on file with the SEC covering resales of the common units to be received by such holders upon any such conversion and (v) EQM has paid all accrued quarterly distributions in cash to the holders. In addition, upon certain events involving a change in control, the holders of Series A Preferred Units may elect, among other potential elections, to convert their preferred units into EQM common units at a certain conversion rate. Shared Assets Transaction. On March 31, 2019, EQM entered into an Assignment and Bill of Sale (the Assignment and Bill of Sale) with the Company pursuant to which EQM acquired certain assets and assumed certain leases that primarily support EQM's operations for an aggregate cash purchase price of $49.7 million (the initial purchase price), which reflected the net book value of in-service assets and expenditures made for assets not yet in-service (collectively, and inclusive of the additional assets subsequently acquired as described in the following sentence, the Shared Assets Transaction). Further, pursuant to the Assignment and Bill of Sale, EQM acquired, effective on the first day of the second quarter of 2019 , certain additional assets from the Company for $8.9 million in cash consideration (the subsequent purchase price), reflecting the net book value of in-service assets and expenditures made in respect of assets not yet in-service as of June 30, 2019 , which subsequent purchase price is subject to certain adjustments. EQM may, pursuant to the Assignment and Bill of Sale, acquire certain additional assets from the Company for additional cash consideration reflecting the net book value of in-service assets and expenditures made with respect to assets not yet in-service and/or may assume an additional facilities lease. The initial and subsequent purchase prices were funded utilizing the EQM Credit Facility (defined in Note 10 ). Prior to the Shared Assets Transaction, EQM made quarterly payments to the Company based on fees allocated from the Company for use of in-service assets transferred to EQM in the Shared Assets Transaction. In connection with the entry into the Assignment and Bill of Sale, the omnibus agreement (ETRN Omnibus Agreement) among the Company, EQM and the New EQM General Partner (as successor to the Former EQM General Partner) was amended and restated in order to, among other things, govern the Company’s use, and payment for such use, of the acquired assets following their conveyance to EQM and provide for reimbursement of EQM by the Company for expenses incurred by EQM in connection with such use. EQM Cash Distribution. On July 24, 2019 , the Board of Directors of the New EQM General Partner declared a cash distribution to EQM's unitholders for the second quarter of 2019 of $1.160 per EQM common unit. The cash distribution will be paid on August 13, 2019 to EQM's common unitholders of record at the close of business on August 2, 2019 . Based on the EQM common units outstanding on July 30, 2019 , cash distributions paid by EQM to the Company will be approximately $136.0 million with respect to the Company's limited partner interest in EQM. In addition, on July 24, 2019 , the Board of Directors of the New EQM General Partner declared a quarterly cash distribution on the Series A Preferred Units for the second quarter of 2019 of $0.9339 per Series A Preferred Unit, which amount reflected pro-ration in accordance with the Fourth Amended and Restated Agreement of Limited Partnership of EQM dated April 10, 2019 . The cash distribution will be paid on August 13, 2019 to Series A preferred unitholders of record at the close of business on August 2, 2019 . For the quarter ended June 30, 2019 , no distributions were declared on the Class B units as none of these units were convertible into EQM common units.

2019 Acquisitions

2019 Acquisitions	6 Months Ended
	Jun. 30, 2019
Business Combinations [Abstract]
2019 Acquisitions	2019 Acquisitions Bolt-on Acquisition. On March 13, 2019, EQM entered into a Purchase and Sale Agreement (the Purchase and Sale Agreement) with North Haven Infrastructure Partners II Buffalo Holdings, LLC (NHIP), an affiliate of Morgan Stanley Infrastructure Partners, pursuant to which EQM acquired from NHIP a 60% Class A interest in Eureka Midstream and a 100% interest in Hornet Midstream Holdings, LLC (Hornet Midstream) (collectively, the Bolt-on Acquisition) for total consideration of approximately $1.03 billion , composed of approximately $864 million in cash and approximately $167 million in assumed pro-rata debt, subject to certain adjustments set forth in the Purchase and Sale Agreement. Eureka Midstream owns a 190 -mile gathering header pipeline system in Ohio and West Virginia that services both dry Utica and wet Marcellus Shale production. Hornet Midstream owns a 15 -mile, high-pressure gathering system in West Virginia that connects to the Eureka Midstream system. The Bolt-on Acquisition closed on April 10, 2019 and was funded through proceeds from the Private Placement of Series A Preferred Units that closed concurrently with the Bolt-on Acquisition. See Note 2 for further information regarding the Private Placement. On the closing of the Bolt-on Acquisition, a subsidiary of Hornet Midstream terminated all of its obligations under its term loan credit agreement and repaid the $28.2 million outstanding principal balance and $0.1 million in related interest and fees. The Company recorded $15.2 million and $16.7 million in acquisition-related expenses related to the Bolt-on Acquisition during the three and six months ended June 30, 2019 , respectively. The Bolt-on Acquisition acquisition-related expenses included $13.5 million for professional fees and $1.7 million for compensation arrangements for the three months ended June 30, 2019 and $15.0 million for professional fees and $1.7 million for compensation arrangements for the six months ended June 30, 2019 and are included in separation and other transaction costs in the statements of condensed consolidated comprehensive income. Allocation of Purchase Price. The Bolt-on Acquisition was accounted for as a business combination using the acquisition method. The following table summarizes the preliminary purchase price and preliminary estimated fair values of assets and liabilities assumed as of April 10, 2019 , with any excess of purchase price over estimated fair value of the identified net assets acquired recorded as goodwill. The $107.9 million of goodwill has been allocated to the Gathering segment. Such goodwill primarily relates to additional commercial opportunities, a diversified producer customer mix, increased exposure to dry Utica and wet Marcellus acreage and operating leverage within the Gathering segment. The purchase price remains subject to post-closing purchase price adjustments; thus, the purchase price adjustments included in the financial statements are preliminary as of June 30, 2019 . The Company expects to complete the purchase price allocation once the Company has received all of the necessary information, at which time the value of the assets and liabilities will be revised as appropriate. The following table summarizes the allocation of the fair value of the assets and liabilities of the Bolt-on Acquisition as of April 10, 2019 by the Company. (in thousands) Preliminary Purchase Price Allocation Consideration given: Cash consideration $ 861,250 Buyout of Eureka Class B Units and incentive compensation 2,530 Total consideration 863,780 Fair value of liabilities assumed: Current liabilities 52,458 Long-term debt 300,825 Other long-term liabilities 10,203 Amount attributable to liabilities assumed 363,486 Fair value of assets acquired: Cash 15,145 Accounts receivable 16,817 Inventory 12,991 Other current assets 882 Net property, plant and equipment 1,222,284 Intangible assets 317,000 Deferred tax asset 5,773 Other assets 14,567 Amount attributable to assets acquired 1,605,459 Noncontrolling interests (486,062 ) Goodwill $ 107,869 The estimated fair value of midstream facilities and equipment, generally consisting of pipeline systems and compression stations, was estimated using the cost approach. Significant unobservable inputs in the estimate of fair value include management's assumptions about the replacement costs for similar assets, the relative age of the acquired assets and any potential economic or functional obsolescence associated with the acquired assets. As a result, the estimated fair value of the midstream facilities and equipment represent a Level 3 fair value measurement. The noncontrolling interest in Eureka Midstream is estimated to be $486.1 million . The fair value of the noncontrolling interest was calculated based on the enterprise value of Eureka Midstream and the percentage ownership not acquired by EQM. Significant unobservable inputs in the enterprise value of Eureka Midstream include future revenue estimates and future cost assumptions, which remain subject to future refinement. As a result, the fair value measurement is based on significant inputs that are not observable in the market and thus represents a Level 3 fair value measurement. As part of the preliminary purchase price allocation, the Company identified intangible assets for customer relationships with third-party customers. The fair value of the customer relationships with third-party customers was determined using the income approach, which requires a forecast of the expected future cash flows generated and an estimated market-based weighted average cost of capital. Significant unobservable inputs in the determination of fair value include future revenue estimates, future cost assumptions and estimated customer retention rates. As a result, the estimated fair value of the identified intangible assets represents a Level 3 fair value measurement. Differences between the preliminary purchase price allocation and the final purchase price allocation may change the amount of intangible assets and goodwill ultimately recognized in conjunction with the Bolt-on Acquisition. The Company calculates amortization of intangible assets using the straight-line method over the estimated useful life of the intangible assets which is 20 years . Amortization expense recorded in the consolidated statements of comprehensive income for the three and six months ended June 30, 2019 was $3.4 million . The estimated annual amortization expense over the next five years is as follows: 2019 $8.1 million , 2020 $15.8 million , 2021 $15.8 million , 2022 $15.8 million and 2023 $15.8 million . Intangible assets, net as of June 30, 2019 are detailed below. (in thousands) As of June 30, 2019 Intangible assets 317,000 Less: accumulated amortization 3,375 Intangible assets, net $ 313,625 In conjunction with the Bolt-on Acquisition, the Company has tax deductible goodwill of $23.1 million . The Company does not have tax basis on the portion attributable to the noncontrolling limited partners of EQM. Post-Acquisition Operating Results. Subsequent to the completion of the Bolt-on Acquisition, Eureka Midstream and Hornet Midstream collectively contributed the following to both the Gathering segment and the Company's consolidated operating results for the period from April 10, 2019 through June 30, 2019 . (in thousands) (unaudited) April 10, 2019 through June 30, 2019 Operating revenues $ 28,928 Operating income attributable to Equitrans Midstream $ 12,496 Net income attributable to noncontrolling interests $ 4,033 Net income attributable to Equitrans Midstream $ 6,506 Unaudited Pro Forma Information. The following unaudited pro forma combined financial information presents the Company's results as though the EQGP Buyout, EQM IDR Transaction and Bolt-on Acquisition had been completed at January 1, 2018. The pro forma combined financial information has been included for comparative purposes and is not necessarily indicative of the results that might have actually occurred had the EQGP Buyout, EQM IDR Transaction and Bolt-on Acquisition taken place on January 1, 2018; furthermore, the financial information is not intended to be a projection of future results. (in thousands, except per share data) (unaudited) Three Months Ended March 31, 2019 Pro forma operating revenues $ 421,362 Pro forma net income $ 208,922 Pro forma net income attributable to noncontrolling interests $ 97,644 Pro forma net income attributable to Equitrans Midstream $ 111,278 Pro forma income per share (basic) $ 0.44 Pro forma income per share (diluted) $ 0.44 (in thousands, except per share data) (unaudited) Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 Pro forma operating revenues $ 406,920 $ 803,945 Pro forma net income $ 213,071 $ 426,212 Pro forma net income attributable to noncontrolling interests $ 89,629 $ 189,036 Pro forma net income attributable to Equitrans Midstream $ 123,442 $ 237,176 Pro forma income per share (basic) $ 0.48 $ 0.93 Pro forma income per share (diluted) $ 0.48 $ 0.93 See Note 2 to the condensed consolidated financial statements for discussions regarding the EQGP Buyout and the EQM IDR Transaction.

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets	6 Months Ended
	Jun. 30, 2019
Property, Plant and Equipment [Abstract]
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates long-lived assets, including related intangibles, for impairment when events or changes in circumstances indicate, in management's judgment, that the carrying value of such assets may not be recoverable. Asset recoverability is measured by comparing the carrying value of the asset or asset group with its expected future pre-tax undiscounted cash flows. These cash flow estimates require the Company to make projections and assumptions for many years into the future for pricing, demand, competition, operating cost and other factors. If the carrying amount exceeds the expected future undiscounted cash flows, the Company recognizes an impairment equal to the excess of net book value over fair value as determined by quoted market prices in active markets or present value techniques if quotes are unavailable. The determination of the fair value using present value techniques requires the Company to make projections and assumptions regarding the probability of a range of outcomes and the rates of interest used in the present value calculations. Any changes the Company makes to these projections and assumptions could result in significant revisions to its evaluation of recoverability of its property, plant and equipment and the recognition of additional impairments. During the second quarter of 2019, the Company reassessed its asset groupings for its regulated pipelines due to certain regulatory ratemaking policy changes affecting the regulated pipelines, changes in strategic focus and plans for segmentation of operations. Prior to the second quarter of 2019, the Company defined its regulated asset grouping to include the FERC-regulated transmission and storage assets, integrated with the low-pressure gathering assets due to overlapping operations, shared costs structure and similar ratemaking structures. During the second quarter, the Company reached a settlement related to its FERC Form 501-G report, which was focused solely on the Company’s FERC-regulated transmission and storage assets. The settlement further differentiated the rate structures, which are primarily negotiated rates for the FERC-regulated transmission assets versus the tariff-based rate structure for the FERC-regulated low-pressure gathering assets. Further, management increased its operational focus and emphasis on high-pressure gathering assets as illustrated by the consummation of the Bolt-on Acquisition. As a result of these regulatory changes and shift in operational focus, beginning with the second quarter of 2019, the Company groups its FERC-regulated assets in two asset groupings: FERC-regulated transmission and storage assets and FERC-regulated low-pressure gathering assets. Upon the change in asset grouping, management evaluated whether any indicators of impairment were present and in conjunction with the evaluation, the Company determined that the carrying values for the non-core FERC-regulated low-pressure gathering assets exceeded their undiscounted cash flows. Additionally, following the settlement related to the FERC Form 501-G report, management does not currently plan to seek to recover the deficient cash flows through a future rate proceeding. The Company therefore estimated the fair values of FERC-related low-pressure gathering assets and determined that their fair values were not in excess of the assets’ carrying values, which resulted in recognized impairments of property and equipment of approximately $80.1 million related to the assets within the Company's Gathering segment. As a result of the impairment, the assets carry no book value.

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases	Leases As discussed in Note 1 , the Company adopted ASU 2016-02, ASU 2018-11 and ASU 2019-01 on January 1, 2019 (the Adoption Date) using the optional transition method of adoption. The Company elected a package of practical expedients that allows an entity to not reassess (i) whether a contract is or contains a lease, (ii) lease classification and (iii) initial direct costs. In addition, the Company elected the following practical expedients: (i) to not reassess certain land easements, (ii) to not apply the recognition requirements under the standard to short-term leases and (iii) to combine and account for lease and nonlease contract components as a lease, which requires the capitalization of fixed nonlease payments on the Adoption Date or lease effective date and the recognition of variable nonlease payments as variable lease expense. Nonlease payments include payments for property taxes and other operating and maintenance expenses incurred by the lessor but payable by the Company in connection with the leasing arrangement. On the Adoption Date, the Company recorded on its consolidated balance sheets an operating lease right-of-use asset and a corresponding operating lease liability of $49.7 million , reflecting the present value of future lease payments on the Company's facility and compressor lease contracts. The discount rate used to determine present value, referred to as the incremental borrowing rate, was based on the rate of interest that the Company estimated it would have to pay to borrow (on a collateralized-basis over a similar term) an amount equal to the lease payments in a similar economic environment as of the Adoption Date. The Company is required to reassess the incremental borrowing rate for any new and modified lease contracts as of the contract effective date. Adoption of the standard did not require an adjustment to the opening balance of retained earnings. As of the Adoption Date and June 30, 2019 , the Company had no lease contracts classified as financing leases and was not a lessor; however, the Company was party to a subleasing arrangement whereby the Company, as sublessor, agreed to sublet office space to a third party. In connection with the Shared Assets Transaction discussed in Note 2 , on March 31, 2019, Equitrans Midstream assigned to EQM two lease agreements that support EQM operations (the Shared Leases Assignment), one of which provides rights to a facility and the other to a compressor station. As a result of the Shared Leases Assignment, EQM recorded $33.0 million of right-of-use assets and corresponding operating lease liabilities. In addition, in connection with the Bolt-on Acquisition discussed in Note 3 , EQM acquired 10 compressor leases and one facilities lease for which it recorded approximately $1.3 million in operating lease expenses during the three and six months ended June 30, 2019 . The Company recorded operating lease right-of-use assets and a corresponding operating lease liability of approximately $20.0 million for these acquired leases. The following table summarizes operating lease cost for the three and six months ended June 30, 2019 . Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (Thousands) Operating lease cost $ 3,407 $ 5,340 Short-term lease cost 1,513 1,918 Variable lease cost 69 82 Sublease (income) (108 ) (192 ) Total lease cost $ 4,881 $ 7,148 Operating lease expense related to the Company's compressor lease contracts and facility lease contracts is reported in operating and maintenance expense and selling, general and administrative expense, respectively, on the Company's statements of condensed consolidated comprehensive income. For the three and six months ended June 30, 2019 , cash paid for operating lease liabilities was $3.1 million and $5.0 million , respectively, which was reported in cash flows provided by operating activities on the statements of condensed consolidated cash flows. The operating lease right-of-use assets are reported in other assets and the current and noncurrent portions of the operating lease liabilities are reported in accrued liabilities and regulatory and other long-term liabilities, respectively, on the Condensed Consolidated Balance Sheets. As of June 30, 2019 , the operating lease right-of-use assets were $66.4 million and operating lease liabilities were $67.1 million , of which $10.7 million was classified as current. As of June 30, 2019 , the weighted average remaining lease term was 9 years and the weighted average discount rate was 6.0% . Schedule of Operating Lease Liability Maturities. The following table summarizes undiscounted cash flows owed by the Company to lessors pursuant to contractual agreements in effect as of June 30, 2019 and related imputed interest. The majority of the Company's lease agreements have multiple renewal periods at the Company's option; however, because none of the renewal periods are reasonably assured to be exercised, the associated operating lease payments have not been included in the table below. June 30, 2019 (Thousands) 2019 $ 6,916 2020 13,237 2021 11,246 2022 9,806 2023 7,747 2024 5,978 Thereafter 30,663 Total 85,593 Less: imputed interest 18,530 Present value of operating lease liability $ 67,063

Financial Information by Busine

Financial Information by Business Segment	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Financial Information by Business Segment	Financial Information by Business Segment The Company, through its control of EQM, reports its operations in three segments that reflect its three lines of business: Gathering, Transmission and Water. Gathering includes EQM's high-pressure gathering lines and FERC-regulated low-pressure gathering lines; Transmission includes EQM's FERC-regulated interstate pipelines and storage system; and Water consists of EQM's water pipelines, impoundment facilities, pumping stations, take point facilities and measurement facilities. As discussed in Note 8 , the 2018 financial statements include expense allocations for certain corporate functions historically performed by EQT. For periods prior to November 12, 2018, the financial statements may not include all expenses that would have been incurred had the Company existed as a standalone, publicly traded corporation for the entirety of such periods. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Revenues from external customers (including related parties): Gathering $ 285,666 $ 241,189 $ 547,547 $ 478,579 Transmission 92,767 89,145 202,626 196,079 Water 27,734 44,363 45,776 71,065 Total operating revenues $ 406,167 $ 374,697 $ 795,949 $ 745,723 Operating income: Gathering $ 94,131 $ 161,818 $ 276,209 $ 332,853 Transmission 63,244 60,642 147,994 140,093 Water 10,072 23,408 11,258 38,720 Other (a) (1,272 ) (11,000 ) (9,245 ) (27,458 ) Total operating income $ 166,175 $ 234,868 $ 426,216 $ 484,208 Reconciliation of operating income to net income: Equity income (b) $ 36,782 $ 10,938 $ 67,845 $ 19,749 Other income 706 944 2,567 1,848 Net interest expense 61,713 19,884 122,662 31,986 Income tax expense 11,470 7,259 43,920 30,468 Net income $ 130,480 $ 219,607 $ 330,046 $ 443,351 (a) Other operating loss includes Separation and other transaction costs and the selling, general and administrative expenses incurred by the Company separate from and in addition to similar costs incurred by EQM. (b) Equity income is included in the Transmission segment. June 30, 2019 December 31, 2018 (Thousands) Segment assets: Gathering $ 8,031,401 $ 6,011,654 Transmission (a) 3,636,355 3,066,659 Water 262,773 237,602 Total operating segments 11,930,529 9,315,915 Headquarters, including cash 505,924 1,207,920 Total assets $ 12,436,453 $ 10,523,835 (a) The equity investment in the MVP Joint Venture is included in the Transmission segment. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Depreciation: Gathering $ 37,443 $ 23,882 $ 65,559 $ 46,950 Transmission 12,594 12,430 25,127 24,871 Water 6,478 5,798 12,894 11,569 Other 244 61 3,690 123 Total $ 56,759 $ 42,171 $ 107,270 $ 83,513 Expenditures for segment assets: Gathering (a) $ 256,318 $ 186,457 $ 414,318 $ 320,595 Transmission (b) 11,229 27,962 29,991 46,891 Water 8,849 7,002 18,024 9,377 Other 2,323 — 5,719 — Total (c) $ 278,719 $ 221,421 $ 468,052 $ 376,863 (a) Includes approximately $10.9 million of capital expenditures related to noncontrolling interests in Eureka Midstream for the three and six months ended June 30, 2019 . (b) Transmission capital expenditures do not include capital contributions made to the MVP Joint Venture for the MVP and MVP Southgate projects of approximately $156.4 million and $65.8 million for the three months ended June 30, 2019 and 2018 , respectively, and approximately $301.2 million and $182.8 million for the six months ended June 30, 2019 and 2018 , respectively. (c) The Company accrues capital expenditures when the work has been completed but the associated bills have not yet been paid. Accrued capital expenditures are excluded from the statements of condensed consolidated cash flows until they are paid. Accrued capital expenditures were approximately $103.6 million , $89.7 million and $109.3 million at June 30, 2019 , March 31, 2019 and December 31, 2018 , respectively. Accrued capital expenditures were approximately $84.6 million , $75.5 million and $90.7 million at June 30, 2018 , March 31, 2018 and December 31, 2017 , respectively. On April 10, 2019, as a result of the Bolt-on Acquisition, the Company assumed $8.8 million of Eureka Midstream accrued capital expenditures.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customers	Revenue from Contracts with Customers For the three and six months ended June 30, 2019 and 2018 , all revenues recognized on the Company's statements of condensed consolidated comprehensive income are from contracts with customers. As of June 30, 2019 and December 31, 2018 , all receivables recorded on the Company's condensed consolidated balance sheets represent performance obligations that have been satisfied and for which an unconditional right to consideration exists. Summary of Disaggregated Revenues. The tables below provide disaggregated revenue information by business segment. Three Months Ended June 30, 2019 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 147,771 $ 81,836 $ — $ 229,607 Volumetric-based fee revenues 137,895 10,931 — 148,826 Water services revenues — — 27,734 27,734 Total operating revenues $ 285,666 $ 92,767 $ 27,734 $ 406,167 Three Months Ended June 30, 2018 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 111,702 $ 82,222 $ — $ 193,924 Volumetric-based fee revenues 129,487 6,923 — 136,410 Water services revenues — — 44,363 44,363 Total operating revenues $ 241,189 $ 89,145 $ 44,363 $ 374,697 Six Months Ended June 30, 2019 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 276,730 $ 181,060 $ — $ 457,790 Volumetric-based fee revenues 270,817 21,566 — 292,383 Water services revenues — — 45,776 45,776 Total operating revenues $ 547,547 $ 202,626 $ 45,776 $ 795,949 Six Months Ended June 30, 2018 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 221,635 $ 179,997 $ — $ 401,632 Volumetric-based fee revenues 256,944 16,082 — 273,026 Water services revenues — — 71,065 71,065 Total operating revenues $ 478,579 $ 196,079 $ 71,065 $ 745,723 Summary of Remaining Performance Obligations. The following table summarizes the transaction price allocated to the Company's remaining performance obligations under all contracts with firm reservation fees and minimum volume commitments (MVCs) as of June 30, 2019 . 2019 (a) 2020 2021 2022 2023 Thereafter Total (Thousands) Gathering firm reservation fees $ 253,531 $ 566,813 $ 614,356 $ 614,356 $ 614,264 $ 2,647,183 $ 5,310,503 Gathering revenues supported by MVCs 45,877 95,294 100,715 100,715 100,715 309,214 752,530 Transmission firm reservation fees 163,370 334,627 345,527 340,453 336,333 2,478,310 3,998,620 Total $ 462,778 $ 996,734 $ 1,060,598 $ 1,055,524 $ 1,051,312 $ 5,434,707 $ 10,061,653 (a) July 1, 2019 through December 31, 2019. Based on total projected contractual revenues, including projected contractual revenues from future capacity expected from expansion projects that are not yet fully constructed for which the Company has executed firm contracts, the Company's firm gathering contracts and firm transmission and storage contracts had weighted average remaining terms of approximately 11 years and 15 years, respectively, as of June 30, 2019 .

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Related Party Transactions with EQT As of June 30, 2019 , EQT remained a related party following the Separation due to its ownership of the Retained Interest. In the ordinary course of business, the Company, through EQM, engaged, and continues to engage, as applicable, in transactions with EQT and its affiliates, including, but not limited to, gathering agreements, transportation service and precedent agreements, storage agreements and water service agreements. EQGP's, EQM's and RMP's Omnibus Agreements with EQT. Prior to the Separation and Distribution, EQGP, EQM and RMP each had an omnibus agreement with EQT. Pursuant to the omnibus agreements, EQT performed centralized corporate general and administrative services for EQGP, EQM and RMP and provided a license for EQGP's and EQM's use of the name "EQT" and related marks in connection with their businesses. EQGP, EQM and RMP reimbursed EQT for the expenses incurred by EQT in providing these services. EQM's and RMP's omnibus agreements also provided for certain indemnification obligations between EQM and RMP, on the one hand, and EQT, on the other hand. On November 12, 2018, EQT terminated the EQGP, EQM and RMP omnibus agreements. Certain indemnification obligations of EQT, EQM and RMP remain in effect following the termination and have been memorialized pursuant to (i) the amended and restated omnibus agreement, dated November 13, 2018, among EQT, EQM and the New EQM General Partner (as successor to the Former EQM General Partner), and (ii) the second amended and restated omnibus agreement, dated November 13, 2018, among EQT, EQT RE, LLC, RM Partners LP (formerly known as Rice Midstream Partners LP), EQM Midstream Management LLC (formerly known as Rice Midstream Management LLC) and EQM Poseidon Midstream LLC (formerly known as Rice Poseidon Midstream LLC). The Company is generally responsible for the surviving obligations of EQT under such agreements pursuant to the Separation and Distribution Agreement. EQGP Working Capital Facility with EQT. See Note 10 . Transition Services Agreement. On November 12, 2018, in connection with the Separation and Distribution, the Company and EQT entered into a transition services agreement (as subsequently amended, the Transition Services Agreement). Pursuant to the Transition Services Agreement, each party agreed to provide certain services to the other on an interim, transitional basis, including services related to information technology, the administration of certain employee benefits and other corporate support services. The Company and EQT agreed to pay the other a fee for these services on a monthly basis. The Transition Services Agreement terminated on June 30, 2019 . Tax Matters Agreement. On November 12, 2018, in connection with the Separation and Distribution, the Company and EQT entered into a tax matters agreement (the Tax Matters Agreement) that governs the parties' respective rights, responsibilities and obligations with respect to taxes (including taxes arising in the ordinary course of business and taxes, if any, incurred as a result of any failure of the Distribution and certain related transactions to qualify as generally tax-free for U.S. federal income tax purposes), tax attributes, the preparation and filing of tax returns, the control of audits and other tax proceedings and assistance and cooperation with respect to tax matters. In addition, the Tax Matters Agreement imposes certain restrictions on the Company and its subsidiaries, including restrictions on equity issuances, business combinations, sales of assets and similar transactions, that are designed to preserve the tax-free status of the Distribution and certain related transactions. The Tax Matters Agreement provides special rules that allocate tax liabilities in the event that the Distribution, together with certain related transactions, is not tax-free. In general, under the Tax Matters Agreement, each party is expected to be responsible for any taxes, whether imposed on the Company or EQT, that arise from (i) the failure of the Distribution, together with certain related transactions, to qualify for tax-free treatment, or (ii) if certain related transactions were to fail to qualify for their intended tax treatment, in each case, to the extent that the failure to qualify is attributable to actions, events or transactions relating to such party's respective stock, assets or business or a breach of the relevant representations or covenants made by that party in the Tax Matters Agreement. Related Party Transactions with EQM and EQGP ETRN Omnibus Agreement. Pursuant to the ETRN Omnibus Agreement, the Company performs centralized corporate, general and administrative services for EQM. In exchange, EQM reimburses the Company for the expenses incurred by the Company in providing these services. In connection with the entry into the Assignment and Bill of Sale, the ETRN Omnibus Agreement was amended and restated, to, among other things, govern the Company's use, and payment for such use, of the acquired assets following their conveyance to EQM. Pursuant to a secondment agreement, employees of the Company and its affiliates may be seconded to EQM to provide operating and other services with respect to EQM's business under the direction, supervision and control of EQM. EQM reimburses the Company and its affiliates for the services provided by the seconded employees. The expenses for which EQM reimburses the Company and its affiliates may not necessarily reflect the actual expenses that EQM would incur on a stand-alone basis. EQM is unable to estimate what those expenses would be on a stand-alone basis. In connection with the Separation, the Company assumed certain obligations from EQT to indemnify and reimburse EQM. For the period from November 13, 2018 through January 10, 2019, EQGP reimbursed the Company for certain expenses related to corporate and general and administrative services provided by the Company pursuant to an omnibus agreement between EQGP and the Company. These expenses may not necessarily reflect the actual expenses that EQGP would have incurred on a stand-alone basis. EQGP is unable to estimate what those costs would have been on a stand-alone basis. The omnibus agreement between EQGP and the Company was terminated on January 10, 2019. See Note 2 . EQGP Working Capital Facility with ETRN. On November 13, 2018, Equitrans Midstream entered into a working capital loan agreement with EQGP (the EQGP Working Capital Facility), through which the Company agreed to make interest-bearing loans available in an aggregate principal amount not to exceed $20 million outstanding at any one time. The EQGP Working Capital Facility was terminated on January 10, 2019. See Note 2 . As of December 31, 2018, EQGP had approximately $1 million of borrowings outstanding under the EQGP Working Capital Facility, all of which was forgiven in connection with the termination of the EQGP Working Capital Facility. During the period from November 13, 2018 through December 31, 2018, the maximum outstanding borrowing was $3.3 million , the average daily balance was approximately $0.9 million and the weighted average annual interest rate was 4.1% .

Investment in Unconsolidated En

Investment in Unconsolidated Entity	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Investment in Unconsolidated Entity	Investment in Unconsolidated Entity The MVP Joint Venture is constructing the Mountain Valley Pipeline (MVP), an estimated 300 -mile natural gas interstate pipeline that will span from northern West Virginia to southern Virginia. EQM is the operator of the MVP and owned a 45.5% interest in the MVP project as of June 30, 2019 . The MVP Joint Venture is a variable interest entity because it has insufficient equity to finance its activities during the construction stage of the project. The Company, through EQM, is not the primary beneficiary of the MVP Joint Venture because the Company does not have the power to direct the activities that most significantly affect the MVP Joint Venture's economic performance. Certain business decisions, such as decisions to make distributions of cash, require a greater than 66 2/3% ownership interest approval, and no one member owns more than a 66 2/3% interest. In April 2018, the MVP Joint Venture announced the MVP Southgate project, a proposed 70 -mile interstate pipeline that will extend from the MVP at Pittsylvania County, Virginia to new delivery points in Rockingham and Alamance Counties, North Carolina. As of June 30, 2019 , EQM had a 47.2% ownership interest in the MVP Southgate project and will operate the pipeline. In May 2019 , the MVP Joint Venture issued a capital call notice for the funding of the MVP project to MVP Holdco, LLC (MVP Holdco), a direct, wholly-owned subsidiary of EQM, for $352.3 million , of which $93.4 million was paid in July 2019 and $114.3 million and $144.5 million is expected to be paid in August 2019 and September 2019 , respectively. In addition, in May 2019 , the MVP Joint Venture issued a capital call notice for the funding of the MVP Southgate project to MVP Holdco for $4.0 million , of which $0.9 million was paid in July 2019 and $1.6 million and $1.5 million is expected to be paid in August 2019 and September 2019 , respectively. The capital contribution payable and the corresponding increase to the investment balance are reflected on the consolidated balance sheet as of June 30, 2019 . The interests in MVP and MVP Southgate are equity method investments for accounting purposes because EQM has the ability to exercise significant influence, but not control, over the MVP Joint Venture's operating and financial policies. Accordingly, EQM records adjustments to the investment balance for contributions to or distributions from the MVP Joint Venture and for EQM's pro-rata share of MVP Joint Venture earnings. Equity income, which is primarily related to EQM's pro-rata share of the MVP Joint Venture's AFUDC on the construction of the MVP, is reported in equity income in the Company's statements of condensed consolidated comprehensive income. Pursuant to the MVP Joint Venture's limited liability company agreement, EQM is obligated to issue a performance guarantee in favor of the MVP Joint Venture to provide performance assurances of MVP Holdco's obligations to fund its proportionate share of the construction budget for the MVP project. In January 2019, EQM issued a performance guarantee in an amount equal to 33% of EQM's proportionate share of the then-remaining construction budget for the MVP project, which was approximately $261 million at the time of issuance. As of June 30, 2019 , EQM was obligated to issue a performance guarantee in an amount equal to approximately $280 million based on the updated construction budget for the MVP project and capital contributions made during the first and second quarters of 2019. Effective July 1, 2019, EQM restated the performance guarantee to an amount equal to approximately $249 million , which reflected a decrease as result of a capital contribution made on July 1, 2019. In addition, in February 2019, EQM issued a performance guarantee of $14 million in favor of the MVP Joint Venture for the MVP Southgate project. Upon the FERC's initial release to begin construction of the MVP Southgate project, EQM's current MVP Southgate performance guarantee will be terminated, and EQM will be obligated to issue a new guarantee in an amount equal to 33% of EQM's proportionate share of the remaining capital obligations for the MVP Southgate project. As of June 30, 2019 , EQM's maximum financial statement exposure related to the MVP Joint Venture was approximately $2,004 million , which consists of the investment in unconsolidated entity balance on the consolidated balance sheet as of June 30, 2019 , net of capital contributions payable, and amounts that could have become due under EQM's performance guarantees as of that date. The following tables summarize the unaudited condensed consolidated financial statements of the MVP Joint Venture. Condensed Consolidated Balance Sheets June 30, 2019 December 31, 2018 (Thousands) Current assets $ 836,397 $ 687,657 Non-current assets 4,033,475 3,223,220 Total assets $ 4,869,872 $ 3,910,877 Current liabilities $ 420,534 $ 617,355 Non-current liabilities 2,166 — Equity 4,447,172 3,293,522 Total liabilities and equity $ 4,869,872 $ 3,910,877 Condensed Statements of Consolidated Operations Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Environmental remediation reserve $ 26 $ — $ (2,166 ) $ — Other income 1,785 743 4,698 1,277 Net interest income 23,700 6,989 43,935 12,638 AFUDC — equity 55,298 16,307 102,514 29,489 Net income $ 80,809 $ 24,039 $ 148,981 $ 43,404

Debt

Debt	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Debt	Debt Equitrans Midstream Credit Facility. In October 2018, Equitrans Midstream entered into a credit facility agreement that provides for $100 million in borrowing capacity and matures in October 2023 (the Equitrans Midstream Credit Facility). Equitrans Midstream amended the Equitrans Midstream Credit Facility on December 31, 2018 to, among other things, permit the incurrence of the borrowings under the Term Loan Credit Agreement (defined herein). The Equitrans Midstream Credit Facility is available for general corporate purposes and to fund ongoing working capital requirements. Subject to satisfaction of certain conditions, the Equitrans Midstream Credit Facility has an accordion feature that allows the Company to increase the available borrowings under the facility by up to an additional $200 million . The Equitrans Midstream Credit Facility has a sublimit of up to $25 million for same-day swing line advances and a sublimit of up to $15 million for letters of credit. The Company had no borrowings outstanding and no letters of credit outstanding under the Equitrans Midstream Credit Facility as of June 30, 2019 . The Company had $17 million of borrowings outstanding and no letters of credit outstanding under the Equitrans Midstream Credit Facility as of December 31, 2018 . During the three and six months ended June 30, 2019 , the maximum outstanding borrowings was $13 million and $44 million , respectively, the average daily balance was approximately $1 million and $6 million , respectively, and the weighted average annual interest rate for both periods was approximately 4.2% . Equitrans Midstream Term Loan Facility . In December 2018, Equitrans Midstream entered into a term loan credit agreement (as amended in May 2019, the Term Loan Credit Agreement) that provides for a senior secured term loan facility in an aggregate principal amount of $600 million and matures in January 2024 (the Term Loans). The Company received net proceeds from the Term Loans of $568.1 million , inclusive of a discount of $18.0 million and estimated debt issuance costs of $13.9 million . The net proceeds were used to fund the EQGP Buyout, including certain fees, costs and expenses in connection therewith, and the remainder was used for general corporate purposes. The Term Loan Credit Agreement provides the Company with the right to request incremental term loans in an aggregate amount of up to $150 million minus the aggregate commitments under the Equitrans Midstream Credit Facility (or any other permitted pari passu revolving credit agreement then in effect), plus the amount of any voluntary prepayment in respect of the Term Loans. The lenders under the Term Loan Credit Agreement are under no obligation to provide such incremental commitments or term loans and any addition of or increase in commitments or term loans is subject to certain customary conditions precedent. As of June 30, 2019 , the current portion of the Term Loans was $6.0 million and is recorded in the current portion of long-term debt on the condensed consolidated balance sheet. The Company had $597.0 million of borrowings outstanding and no letters of credit outstanding under the Term Loan Credit Agreement as of June 30, 2019 . The Company had $600 million of borrowings outstanding and no letters of credit outstanding under the Term Loan Credit Agreement as of December 31, 2018 . During the three and six months ended June 30, 2019 , the weighted average annual interest rate for both periods was approximately 7.0% . EQGP Working Capital Facility with EQT. Prior to the Separation, EQGP had a working capital loan agreement with EQT (the EQGP Working Capital Facility with EQT), through which EQT agreed to make interest-bearing loans available in an aggregate principal amount not to exceed $50 million outstanding at any one time. Borrowings outstanding under the EQGP Working Capital Facility with EQT were presented in accounts payable as an amount due to related party on the condensed consolidated balance sheet. On November 12, 2018, EQGP repaid $3.2 million of borrowings outstanding under the facility, and EQT terminated the working capital loan agreement. During the six months ended June 30, 2018 , the maximum outstanding borrowing was $0.2 million and the weighted average annual interest rate was approximately 3.2% . EQM Revolving Credit Facility. On October 31, 2018, EQM amended and restated its credit facility to increase the borrowing capacity from $1 billion to $3 billion and extend the term to October 2023 (the EQM Credit Facility). The EQM Credit Facility is available for general partnership purposes, including to purchase assets, and to fund working capital requirements and capital expenditures, pay distributions and repurchase units. Subject to satisfaction of certain conditions, the EQM Credit Facility has an accordion feature that allows EQM to increase the available borrowings under the facility by up to an additional $750 million . The EQM Credit Facility has a sublimit of up to $250 million for same-day swing line advances and a sublimit of up to $400 million for letters of credit. In addition, EQM has the ability to request that one or more lenders make available term loans under the EQM Credit Facility, subject to the satisfaction of certain conditions. Such term loans would be secured by cash and qualifying investment grade securities. EQM's obligations under the revolving portion of the EQM Credit Facility are unsecured. The EQM Credit Facility contains negative covenants that, among other things, limit restricted payments, the incurrence of debt, dispositions, mergers and fundamental changes, and transactions with affiliates. In addition, the EQM Credit Facility contains events of default such as insolvency, nonpayment of scheduled principal or interest obligations, change of control and cross-default related to the acceleration or default of certain other financial obligations. Under the EQM Credit Facility, EQM is required to maintain a consolidated leverage ratio of not more than 5.00 to 1.00 (or not more than 5.50 to 1.00 for certain measurement periods following the consummation of certain acquisitions). As of June 30, 2019 , EQM had approximately $1.1 billion of borrowings outstanding and $1 million of letters of credit outstanding under the EQM Credit Facility. As of December 31, 2018 , EQM had approximately $625 million of borrowings outstanding and $1 million of letters of credit outstanding under the EQM Credit Facility. During the three and six months ended June 30, 2019 , the maximum outstanding borrowings was approximately $1.2 billion , the average daily balance was approximately $1,043 million and $993 million , respectively, and the weighted average annual interest rate for the periods was approximately 3.8% and 3.9% , respectively. During the three and six months ended June 30, 2018 , the maximum outstanding borrowings was approximately $338 million and $420 million , respectively, the average daily balance was approximately $122 million and $211 million , respectively, and the weighted average annual interest rate for the periods was approximately 3.4% and 3.2% , respectively. Eureka Credit Facility. Eureka Midstream, LLC (Eureka), a wholly-owned subsidiary of Eureka Midstream, has a $400 million revolving credit facility, which is available for general business purposes, including financing maintenance and expansion capital expenditures related to the Eureka system and providing working capital for Eureka’s operations (the Eureka Credit Facility). Subject to satisfaction of certain conditions, the Eureka Credit Facility has an accordion feature that allows Eureka to increase the available borrowings under the facility by an additional $100 million to an aggregate $500 million of total commitments. Under the terms of the Eureka Credit Facility, Eureka can obtain base rate loans or Eurodollar rate loans. Base rate loans are denominated in dollars and bear interest at an adjusted base rate, which was equal to the higher of (i) JPMorgan Chase Bank, N.A.'s prime rate, (ii) the one-month Adjusted Eurodollar Rate (as defined in the Eureka Credit Facility credit agreement) plus 1.0% or (iii) the Federal Funds effective rate plus 0.5% per annum; plus the Applicable Margin, as described below. Eurodollar rate loans bear interest at the Adjusted Eurodollar Rate per annum, which rate is to be determined by the administrative agent pursuant to a prescribed calculation based on the ICE Benchmark Administration LIBOR Rate plus the Applicable Margin. The Applicable Margin ranged from 0.75% to 2.0% in the case of base rate loans and from 1.75% to 3.0% in the case of Eurodollar loans, in each case, depending on the amount of the loan outstanding in relation to the borrowing base. The Eureka Credit Facility contains negative covenants that, among other things, limit restricted payments, the incurrence of debt, dispositions, mergers and fundamental changes, securities issuances, and transactions with affiliates. In addition, the Eureka Credit Facility contains events of default such as insolvency, nonpayment of scheduled principal or interest obligations, loss of material contracts, change of control and cross-default related to the acceleration or default of certain other financial obligations. Under the Eureka Credit Facility, Eureka is required to maintain a consolidated leverage ratio of not more than 4.75 to 1.00 (or not more than 5.25 to 1.00 for certain measurement periods following the consummation of certain acquisitions). Additionally, as of the end of any fiscal quarter, Eureka will not permit the ratio of consolidated EBITDA (as defined in the Eureka Credit Facility) for the four fiscal quarters then ending to consolidated interest charges to be less than 2.50 to 1.00 . As of June 30, 2019 , Eureka had approximately $293 million of borrowings outstanding under the Eureka Credit Facility. For the period from April 10, 2019 through June 30, 2019 , the maximum amount of outstanding borrowings under the Eureka Credit Facility at any time was approximately $293 million , the average daily balance was approximately $277 million and Eureka incurred interest at a weighted average annual interest rate of approximately 4.5% . EQM Term Loan Facility . On April 25, 2018, EQM entered into a $2.5 billion unsecured multi-draw 364 -day term loan facility with a syndicate of lenders (the EQM Term Loan Facility). The EQM Term Loan Facility was used to fund the cash consideration for the Drop-Down Transaction, to repay borrowings under EQM's then-existing revolving credit facility and for other general partnership purposes. In connection with EQM's issuance of the EQM $2.5 billion Senior Notes (defined below), on June 25, 2018, the balance outstanding under the EQM Term Loan Facility was repaid and the EQM Term Loan Facility was terminated. As a result of the termination, EQM expensed $3 million of deferred issuance costs. From April 25, 2018 through June 25, 2018, the maximum amount of EQM's outstanding borrowings under the EQM Term Loan Facility at any time was approximately $1,825 million and the average daily balance was approximately $1,231 million . EQM incurred interest at a weighted average annual interest rate of approximately 3.3% for the period from April 25, 2018 through June 25, 2018. RMP $850 Million Facility. RM Operating LLC (formerly Rice Midstream OpCo LLC), a wholly-owned subsidiary of RMP, had an $850 million credit facility (the RMP $850 Million Facility). In connection with the completion of the EQM-RMP Mergers, on July 23, 2018 , EQM repaid the approximately $260 million of borrowings outstanding under the RMP $850 Million Facility and the RMP $850 Million Facility was terminated. Prior to its termination, the RMP $850 Million Facility was available for general partnership purposes, including to purchase assets, and to fund working capital requirements and capital expenditures, pay distributions and repurchase units. The RMP $850 Million Facility was secured by mortgages and other security interests on substantially all of RMP's properties and was guaranteed by RMP and its restricted subsidiaries. During the three and six months ended June 30, 2018 , the maximum outstanding borrowings were approximately $325 million and $336 million , respectively, the average daily balance was approximately $305 million and $306 million , respectively, and the weighted average annual interest rate for the period was approximately 3.9% and 3.8% , respectively. EQM 4.125% and 4.00% Senior Notes. In the fourth quarter of 2016, EQM issued $500 million aggregate principal amount of 4.125% senior notes due December 2026 (the 4.125% Senior Notes). EQM used the net proceeds from the offering to repay the then outstanding borrowings under a predecessor to the EQM Credit Facility and for general partnership purposes. In the third quarter of 2014, EQM issued $500 million aggregate principal amount of 4.00% senior notes due August 2024 (the 4.00% Senior Notes). EQM used the net proceeds from the offering to repay the outstanding borrowings under a predecessor to the EQM Credit Facility and for general partnership purposes. Both the 4.125% Senior Notes and the 4.00% Senior Notes contain covenants that limit EQM's ability to, among other things, incur certain liens securing indebtedness, engage in certain sale and leaseback transactions and enter into certain consolidations, mergers, conveyances, transfers or leases of all or substantially all of EQM's assets. EQM $2.5 Billion Senior Notes. During the second quarter of 2018, EQM issued 4.75% senior notes due July 2023 in the aggregate principal amount of $1.1 billion , 5.50% senior notes due July 2028 in the aggregate principal amount of $850 million and 6.50% senior notes due July 2048 in the aggregate principal amount of $550 million (collectively, the EQM $2.5 Billion Senior Notes). EQM received net proceeds from the offering of approximately $2,465.8 million , inclusive of a discount of $11.8 million and estimated debt issuance costs of approximately $22.4 million . The net proceeds were used to repay the outstanding balances under the EQM Term Loan Facility and the RMP $850 Million Facility, and the remainder was used for general partnership purposes. The EQM $2.5 Billion Senior Notes were issued pursuant to new supplemental indentures to EQM's existing indenture dated August 1, 2014. The EQM $2.5 Billion Senior Notes contain covenants that limit EQM's ability to, among other things, incur certain liens securing indebtedness, engage in certain sale and leaseback transactions and enter into certain consolidations, mergers, conveyances, transfers or leases of all or substantially all of EQM's assets. As of June 30, 2019 , Equitrans Midstream, EQM and Eureka were in compliance with all debt provisions and covenants.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The carrying values of cash and cash equivalents, accounts receivable, amounts due to/from related parties and accounts payable approximate fair value due to the short maturity of the instruments; as such, their fair values are Level 1 fair value measurements. The carrying value of the credit facility borrowings approximates fair value as the interest rates are based on prevailing market rates; this is considered a Level 1 fair value measurement. As the Company's borrowings under the Term Loan Credit Agreement and EQM's senior notes are not actively traded, their fair values are estimated using an income approach model that applies a discount rate based on prevailing market rates for debt with similar remaining time-to-maturity and credit risk; as such, their fair values are Level 2 fair value measurements. As of June 30, 2019 and December 31, 2018 , the estimated fair value of the Company's borrowings under the Term Loan Credit Agreement was approximately $604 million and $590 million , respectively, and the carrying value of the Company's borrowings under the Term Loan Credit Agreement was approximately $568 million for both periods. As of June 30, 2019 and December 31, 2018 , the estimated fair value of EQM's senior notes was approximately $3,612 million and $3,425 million , respectively, and the carrying value of EQM's senior notes was approximately $3,459 million and $3,457 million , respectively. The fair value of the Preferred Interest is a Level 3 fair value measurement and is estimated using an income approach model that applies a market-based discount rate. As of June 30, 2019 and December 31, 2018 , the estimated fair value of the Preferred Interest was approximately $127 million and $122 million , respectively, and the carrying value of the Preferred Interest was approximately $112 million and $115 million , respectively.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share In connection with the Distribution described in Note 1 , and based on the 254,586,700 shares of outstanding common stock of EQT (EQT common stock) as of the record date for the Distribution, the Company issued 254,268,864 shares of Equitrans Midstream common stock. As of June 30, 2019 , there were 254,691,255 shares of Equitrans Midstream common stock outstanding, of which EQT owned 50,599,503 . Potentially dilutive securities (options and restricted awards) included in the calculation of diluted earnings per share totaled 49,458 and 601,622 for the three months ended June 30, 2019 and 2018 , respectively, and 50,167 and 601,622 for the six months ended June 30, 2019 and 2018 , respectively. The impact of EQM's dilutive units did not have a material impact on the Company's earnings per share calculations for any of the periods presented. For periods prior to the Separation Date, earnings per share shown on the statements of condensed consolidated comprehensive income were calculated based on the shares of Equitrans Midstream common stock distributed in connection with the Separation and Distribution and is considered pro forma in nature. Prior to the Separation Date, the Company did not have any issued or outstanding common stock (other than shares owned by EQT).

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rate was 8.1% for the three months ended June 30, 2019 , compared to 3.2% for the three months ended June 30, 2018 . The effective tax rate was 11.7% for the six months ended June 30, 2019 , compared to 6.4% for the six months ended June 30, 2018 . The effective tax rate was higher for both the three and six months ended June 30, 2019 compared to the three and six months ended June 30, 2018 due to Rice Midstream Holdings' income not subject to tax expense and due to higher income attributable to noncontrolling limited partners in 2018 . Prior to October 22, 2018, Rice Midstream Holdings was a multi-member limited liability company; therefore, the earnings of Rice Midstream Holdings and its subsidiaries were not subject to federal income tax. In the fourth quarter of 2018 , Rice Midstream Holdings was merged out of existence as part of internal restructurings. Excluding other items, the effective tax rates for both periods are lower than the statutory rates because the Company does not record income tax expense on the portion of its income attributable to the noncontrolling limited partners of EQM, the noncontrolling members of Eureka Midstream and, for the period prior to the Limited Call Right, the noncontrolling limited partners of EQGP.

Consolidated Variable Interest

Consolidated Variable Interest Entities	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidated Variable Interest Entities	Consolidated Variable Interest Entities As of June 30, 2019 , the Company determined EQM to be a variable interest entity. In addition, as of December 31, 2018, EQGP was also a variable interest entity. Through the Company's ownership and control of the general partners of EQGP and EQM, the Company had the power to direct the activities that most significantly affected EQGP's and EQM's economic performance during the periods presented. Through its limited and general partner interests in EQGP prior to the EQM IDR Transaction, its limited partner interest in EQM and through EQGP's general partner interest, limited partner interest and IDRs in EQM prior to the EQM IDR Transaction, the Company had the right to receive benefits from, as well as the obligation to absorb the losses of, EQGP and EQM. On January 10, 2019, following the completion of the EQGP Buyout, EQGP became an indirect, wholly-owned subsidiary of the Company. As the Company is the primary beneficiary of and has a controlling financial interest in EQGP and EQM, the Company consolidated EQGP, which, prior to the EQGP Buyout, consolidated EQM for the periods presented. See Note 2 . In addition, for discussion of related party transactions, see Note 8 . The Company continues to consolidate EQM. The risks associated with the operations of EQM are discussed in its Annual Report on Form 10-K for the year ended December 31, 2018 , as updated by any Quarterly Reports on Form 10-Q. See further discussion of the impact that Equitrans Midstream's ownership and control of EQM had on Equitrans Midstream's financial position, results of operations and cash flows included in Equitrans Midstream's Annual Report on Form 10-K for the year ended December 31, 2018 , as updated by any Quarterly Reports on Form 10-Q, including in the sections captioned "Management's Discussion and Analysis of Financial Condition and Results of Operations." The following table presents assets and liabilities included in the Company's consolidated balance sheets that were for the use or obligation of EQM, inclusive of receivables and payables due from or to related parties. June 30, 2019 December 31, 2018 (Thousands) ASSETS Cash and cash equivalents $ 16,625 $ 17,515 Accounts receivable (a) 274,790 254,390 Other current assets 21,971 14,909 Net property, plant and equipment (b) 7,375,142 5,806,628 Investment in unconsolidated entity 2,066,330 1,510,289 Goodwill 1,237,456 1,123,813 Net intangible assets 868,965 576,113 Other assets 201,891 152,464 LIABILITIES Accounts payable (a) $ 179,448 $ 207,877 Capital contribution payable to the MVP Joint Venture 356,223 169,202 Accrued interest 73,443 80,199 Accrued liabilities 38,265 20,672 Credit facility borrowings 1,372,500 625,000 EQM Senior notes 3,459,323 3,456,639 Regulatory and other long-term liabilities 81,093 38,724 (a) Accounts receivable as of June 30, 2019 and December 31, 2018 included $126.7 million and $174.8 million , respectively, of receivables due from EQT. Accounts payable as of December 31, 2018 included approximately $34.0 million of related party accounts payable to EQT. There was no related party balance with EQT included in accounts payable as of June 30, 2019 . (b) Includes approximately $58.6 million conveyed to EQM in the Shared Assets Transaction primarily consisting of IT infrastructure, office equipment, vehicles and office leases. See Note 2 . The following table summarizes EQM's statements of consolidated operations and cash flows, inclusive of transactions with related parties. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Operating revenues $ 406,167 $ 374,697 $ 795,949 $ 745,723 Operating expenses 238,720 128,829 360,488 234,057 Other expenses, net (10,976 ) (11,183 ) (27,059 ) (14,138 ) Net income $ 156,471 $ 234,685 $ 408,402 $ 497,528 Net cash provided by operating activities $ 349,270 $ 338,950 $ 510,243 $ 622,907 Net cash used in investing activities $ (1,324,948 ) $ (1,470,210 ) $ (1,675,305 ) $ (1,756,739 ) Net cash provided by financing activities $ 918,464 $ 1,751,298 $ 1,164,172 $ 1,780,686

Financial Statements (Policies)

Financial Statements (Policies)	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation. As of December 31, 2018, the Former EQGP General Partner was a wholly-owned subsidiary of Equitrans Gathering and controlled EQGP through its general partner interest in EQGP; therefore, the financial statements of Equitrans Midstream consolidated and, following the closing of the EQGP Unit Purchases and the exercise of the Limited Call Right, continue to consolidate EQGP. As of December 31, 2018, the Former EQM General Partner was a wholly-owned subsidiary of EQGP and controlled EQM through its general partner interest in EQM; therefore, the financial statements of EQGP consolidated EQM. For each of the periods prior to the Separation presented in this Quarterly Report on Form 10-Q, the consolidated financial statements and related notes include the assets, liabilities and results of operations of the Midstream Business that were transferred to Equitrans Midstream upon the closing of the Distribution and represent the predecessor for accounting purposes of Equitrans Midstream (the Predecessor). References in these financial statements to Equitrans Midstream or the Company refer collectively to Equitrans Midstream Corporation and the Predecessor as applicable for all periods presented. Predecessor financial information has been derived from EQT's consolidated financial statements and accounting records and reflects the historical results of operations, financial position and cash flows of the Company as if the Midstream Business had been consolidated for all periods presented. The financial statements include expense allocations for certain corporate functions historically performed by EQT, such as executive oversight, accounting, treasury, tax, legal, supply chain, information technology and share-based compensation. See Note 8 . The Company believes the assumptions underlying the consolidated financial statements are reasonable; however, as organizational structure and strategic focus dictate expenses incurred, the financial statements may not include all expenses that would have been incurred had the Company existed as a standalone, publicly traded company for the six months ended June 30, 2018 . Similarly, the financial statements may not reflect the results of operations, financial position and cash flows had the Company existed as a standalone, publicly traded company during that period. Following the completion of the Bolt-on Acquisition, the Company, through EQM, evaluated Eureka Midstream Holdings, LLC (Eureka Midstream) for consolidation and determined that Eureka Midstream does not meet the criteria for variable interest entity classification due to its ability to independently finance its operations through the Eureka Credit Facility (as defined in Note 10 ), as well as each member having proportional voting rights through their equity investments. As such, as of June 30, 2019 , EQM consolidates Eureka Midstream using the voting interest model, recording noncontrolling interest related to the third-party ownership interests in Eureka Midstream. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the requirements of Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, these unaudited condensed consolidated financial statements include all adjustments (consisting of only normal, recurring adjustments, unless otherwise disclosed in this Form 10-Q) necessary for a fair presentation of the financial position of the Company as of June 30, 2019 and December 31, 2018 , the results of its operations and its equity for the three and six months ended June 30, 2019 and 2018 and its cash flows for the six months ended June 30, 2019 and 2018 . The condensed consolidated balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and notes required by GAAP for complete financial statements. Due to the seasonal nature of EQM's utility customer contracts, the interim statements for the three and six months ended June 30, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 . For further information, refer to the Company's annual combined consolidated financial statements and related notes for the year ended December 31, 2018 , as well as "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained therein.
Recently Issued Accounting Standards	Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases . The standard requires entities to record assets and obligations for contracts currently recognized as operating leases. In July 2018, the FASB issued ASU 2018-11, Leases (Topic 842): Targeted Improvements . The update provides an optional transition method of adoption that permits entities to initially apply the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Under the optional transition method, comparative financial information and disclosures are not required. The update also provides transition practical expedients. The standard requires disclosures of the nature, maturity and value of an entity's lease liabilities and elections taken by the entity. In March 2019, the FASB issued ASU 2019-01, Leases (Topic 842): Codification Improvements , which, among other things, clarifies interim disclosure requirements in the year of ASU 2016-02 adoption. The Company adopted ASU 2016-02, ASU 2018-11 and ASU 2019-01 on January 1, 2019 using the optional transition method. The Company uses a lease accounting system to monitor its current population of lease contracts. The Company implemented processes and controls to review new lease contracts for appropriate accounting treatment in the context of the standards and to generate disclosures required under the standards. For the disclosures required by the standards, see Note 5 . In June 2016, the FASB issued ASU 2016-13, Financial Instruments — Credit Losses: Measurement of Credit Losses on Financial Instruments . The standard amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this standard eliminates the probable initial recognition threshold in current GAAP and, in its place, requires an entity to recognize its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposures, reinsurance receivables and any other financial assets not excluded from the scope of the standard that have the contractual right to receive cash. The standard will be effective for annual reporting periods beginning after December 15, 2019, including interim periods within that reporting period. The Company is currently evaluating the effect this standard will have on its financial statements and related disclosures. In February 2018, the FASB issued ASU 2018-02, Income Statement, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which allows for a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act and will improve the usefulness of information reported to financial statement users. The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company adopted the standard in the first quarter of 2019 with no significant effect on its financial statements or related disclosures. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement, Changes to the Disclosure Requirements for Fair Value Measurement , which makes a number of changes to the hierarchy associated with Level 1, 2 and 3 fair value measurements and the related disclosure requirements. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. The Company is currently evaluating the effect this standard will have on its financial statements and related disclosures but does not expect the adoption of this standard to have a material effect on its financial statements and related disclosures. In August 2018, the FASB issued ASU 2018-15, Intangibles—Goodwill and Other: Internal-Use Software , which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company early-adopted the standard using the prospective method of adoption on January 1, 2019. Following the adoption of ASU 2018-15, the Company began capitalizing certain implementation costs related to cloud computing arrangements that are service contracts. The capitalized portion of these costs are included in the property, plant and equipment line on the consolidated balance sheets and will be amortized over the term of the Company's hosting arrangement, which has a fixed term of seven years . For the three and six months ended June 30, 2019 , the Company did no t recognize any amortization expense related to implementation costs on its cloud computing arrangements as such assets were not in use. The costs will be included in the selling, general and administrative expense line on the accompanying statements of consolidated comprehensive income when recognized. In August 2018, the U.S. Securities and Exchange Commission (SEC) adopted a final rule under SEC Release No. 33-10532, Disclosure Update and Simplification , that amends certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. The amendments also expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements, in that registrants must now analyze changes in stockholders’ equity, in the form of reconciliation, for the current and comparative year-to-date periods, with subtotals for each interim period. This final rule was effective on November 5, 2018 and the Company assessed the impact on its consolidated financial statements disclosures to be not significant. The Company adopted the final rule and began applying this disclosure change to its statement of condensed consolidated equity in the first quarter of 2019.
Impairment Long-Lived Assets	The Company evaluates long-lived assets, including related intangibles, for impairment when events or changes in circumstances indicate, in management's judgment, that the carrying value of such assets may not be recoverable. Asset recoverability is measured by comparing the carrying value of the asset or asset group with its expected future pre-tax undiscounted cash flows. These cash flow estimates require the Company to make projections and assumptions for many years into the future for pricing, demand, competition, operating cost and other factors. If the carrying amount exceeds the expected future undiscounted cash flows, the Company recognizes an impairment equal to the excess of net book value over fair value as determined by quoted market prices in active markets or present value techniques if quotes are unavailable. The determination of the fair value using present value techniques requires the Company to make projections and assumptions regarding the probability of a range of outcomes and the rates of interest used in the present value calculations. Any changes the Company makes to these projections and assumptions could result in significant revisions to its evaluation of recoverability of its property, plant and equipment and the recognition of additional impairments.

2019 Acquisitions (Tables)

2019 Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2019
Business Combinations [Abstract]
Schedule of Preliminary Purchase Price Allocations	The following table summarizes the allocation of the fair value of the assets and liabilities of the Bolt-on Acquisition as of April 10, 2019 by the Company. (in thousands) Preliminary Purchase Price Allocation Consideration given: Cash consideration $ 861,250 Buyout of Eureka Class B Units and incentive compensation 2,530 Total consideration 863,780 Fair value of liabilities assumed: Current liabilities 52,458 Long-term debt 300,825 Other long-term liabilities 10,203 Amount attributable to liabilities assumed 363,486 Fair value of assets acquired: Cash 15,145 Accounts receivable 16,817 Inventory 12,991 Other current assets 882 Net property, plant and equipment 1,222,284 Intangible assets 317,000 Deferred tax asset 5,773 Other assets 14,567 Amount attributable to assets acquired 1,605,459 Noncontrolling interests (486,062 ) Goodwill $ 107,869
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	(in thousands) As of June 30, 2019 Intangible assets 317,000 Less: accumulated amortization 3,375 Intangible assets, net $ 313,625
Schedule of Post-Acquisition Operating Results and Unaudited Pro Forma Information	The following unaudited pro forma combined financial information presents the Company's results as though the EQGP Buyout, EQM IDR Transaction and Bolt-on Acquisition had been completed at January 1, 2018. The pro forma combined financial information has been included for comparative purposes and is not necessarily indicative of the results that might have actually occurred had the EQGP Buyout, EQM IDR Transaction and Bolt-on Acquisition taken place on January 1, 2018; furthermore, the financial information is not intended to be a projection of future results. (in thousands, except per share data) (unaudited) Three Months Ended March 31, 2019 Pro forma operating revenues $ 421,362 Pro forma net income $ 208,922 Pro forma net income attributable to noncontrolling interests $ 97,644 Pro forma net income attributable to Equitrans Midstream $ 111,278 Pro forma income per share (basic) $ 0.44 Pro forma income per share (diluted) $ 0.44 (in thousands, except per share data) (unaudited) Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 Pro forma operating revenues $ 406,920 $ 803,945 Pro forma net income $ 213,071 $ 426,212 Pro forma net income attributable to noncontrolling interests $ 89,629 $ 189,036 Pro forma net income attributable to Equitrans Midstream $ 123,442 $ 237,176 Pro forma income per share (basic) $ 0.48 $ 0.93 Pro forma income per share (diluted) $ 0.48 $ 0.93 See Note 2 to the condensed consolidated financial statements for discussions regarding the EQGP Buyout and the EQM IDR Transaction. Subsequent to the completion of the Bolt-on Acquisition, Eureka Midstream and Hornet Midstream collectively contributed the following to both the Gathering segment and the Company's consolidated operating results for the period from April 10, 2019 through June 30, 2019 . (in thousands) (unaudited) April 10, 2019 through June 30, 2019 Operating revenues $ 28,928 Operating income attributable to Equitrans Midstream $ 12,496 Net income attributable to noncontrolling interests $ 4,033 Net income attributable to Equitrans Midstream $ 6,506

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Schedule of Operating Lease Cost	The following table summarizes operating lease cost for the three and six months ended June 30, 2019 . Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (Thousands) Operating lease cost $ 3,407 $ 5,340 Short-term lease cost 1,513 1,918 Variable lease cost 69 82 Sublease (income) (108 ) (192 ) Total lease cost $ 4,881 $ 7,148
Schedule of Operating Lease Liability Maturities	The following table summarizes undiscounted cash flows owed by the Company to lessors pursuant to contractual agreements in effect as of June 30, 2019 and related imputed interest. The majority of the Company's lease agreements have multiple renewal periods at the Company's option; however, because none of the renewal periods are reasonably assured to be exercised, the associated operating lease payments have not been included in the table below. June 30, 2019 (Thousands) 2019 $ 6,916 2020 13,237 2021 11,246 2022 9,806 2023 7,747 2024 5,978 Thereafter 30,663 Total 85,593 Less: imputed interest 18,530 Present value of operating lease liability $ 67,063

Financial Information by Busi_2

Financial Information by Business Segment (Tables)	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Schedule of Revenue from External Customers and Operating Income and Reconciliation to Net Income	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Revenues from external customers (including related parties): Gathering $ 285,666 $ 241,189 $ 547,547 $ 478,579 Transmission 92,767 89,145 202,626 196,079 Water 27,734 44,363 45,776 71,065 Total operating revenues $ 406,167 $ 374,697 $ 795,949 $ 745,723 Operating income: Gathering $ 94,131 $ 161,818 $ 276,209 $ 332,853 Transmission 63,244 60,642 147,994 140,093 Water 10,072 23,408 11,258 38,720 Other (a) (1,272 ) (11,000 ) (9,245 ) (27,458 ) Total operating income $ 166,175 $ 234,868 $ 426,216 $ 484,208 Reconciliation of operating income to net income: Equity income (b) $ 36,782 $ 10,938 $ 67,845 $ 19,749 Other income 706 944 2,567 1,848 Net interest expense 61,713 19,884 122,662 31,986 Income tax expense 11,470 7,259 43,920 30,468 Net income $ 130,480 $ 219,607 $ 330,046 $ 443,351 (a) Other operating loss includes Separation and other transaction costs and the selling, general and administrative expenses incurred by the Company separate from and in addition to similar costs incurred by EQM. (b) Equity income is included in the Transmission segment.
Schedule of Segment Assets	June 30, 2019 December 31, 2018 (Thousands) Segment assets: Gathering $ 8,031,401 $ 6,011,654 Transmission (a) 3,636,355 3,066,659 Water 262,773 237,602 Total operating segments 11,930,529 9,315,915 Headquarters, including cash 505,924 1,207,920 Total assets $ 12,436,453 $ 10,523,835 (a) The equity investment in the MVP Joint Venture is included in the Transmission segment.
Schedule of Depreciation and Amortization and Expenditures for Segment Assets	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Depreciation: Gathering $ 37,443 $ 23,882 $ 65,559 $ 46,950 Transmission 12,594 12,430 25,127 24,871 Water 6,478 5,798 12,894 11,569 Other 244 61 3,690 123 Total $ 56,759 $ 42,171 $ 107,270 $ 83,513 Expenditures for segment assets: Gathering (a) $ 256,318 $ 186,457 $ 414,318 $ 320,595 Transmission (b) 11,229 27,962 29,991 46,891 Water 8,849 7,002 18,024 9,377 Other 2,323 — 5,719 — Total (c) $ 278,719 $ 221,421 $ 468,052 $ 376,863 (a) Includes approximately $10.9 million of capital expenditures related to noncontrolling interests in Eureka Midstream for the three and six months ended June 30, 2019 . (b) Transmission capital expenditures do not include capital contributions made to the MVP Joint Venture for the MVP and MVP Southgate projects of approximately $156.4 million and $65.8 million for the three months ended June 30, 2019 and 2018 , respectively, and approximately $301.2 million and $182.8 million for the six months ended June 30, 2019 and 2018 , respectively. (c) The Company accrues capital expenditures when the work has been completed but the associated bills have not yet been paid. Accrued capital expenditures are excluded from the statements of condensed consolidated cash flows until they are paid. Accrued capital expenditures were approximately $103.6 million , $89.7 million and $109.3 million at June 30, 2019 , March 31, 2019 and December 31, 2018 , respectively. Accrued capital expenditures were approximately $84.6 million , $75.5 million and $90.7 million at June 30, 2018 , March 31, 2018 and December 31, 2017 , respectively. On April 10, 2019, as a result of the Bolt-on Acquisition, the Company assumed $8.8 million of Eureka Midstream accrued capital expenditures.

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregated Revenue Information, by Business Segment	The tables below provide disaggregated revenue information by business segment. Three Months Ended June 30, 2019 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 147,771 $ 81,836 $ — $ 229,607 Volumetric-based fee revenues 137,895 10,931 — 148,826 Water services revenues — — 27,734 27,734 Total operating revenues $ 285,666 $ 92,767 $ 27,734 $ 406,167 Three Months Ended June 30, 2018 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 111,702 $ 82,222 $ — $ 193,924 Volumetric-based fee revenues 129,487 6,923 — 136,410 Water services revenues — — 44,363 44,363 Total operating revenues $ 241,189 $ 89,145 $ 44,363 $ 374,697 Six Months Ended June 30, 2019 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 276,730 $ 181,060 $ — $ 457,790 Volumetric-based fee revenues 270,817 21,566 — 292,383 Water services revenues — — 45,776 45,776 Total operating revenues $ 547,547 $ 202,626 $ 45,776 $ 795,949 Six Months Ended June 30, 2018 Gathering Transmission Water Total (Thousands) Firm reservation fee revenues $ 221,635 $ 179,997 $ — $ 401,632 Volumetric-based fee revenues 256,944 16,082 — 273,026 Water services revenues — — 71,065 71,065 Total operating revenues $ 478,579 $ 196,079 $ 71,065 $ 745,723
Summary of Remaining Performance Obligations	The following table summarizes the transaction price allocated to the Company's remaining performance obligations under all contracts with firm reservation fees and minimum volume commitments (MVCs) as of June 30, 2019 . 2019 (a) 2020 2021 2022 2023 Thereafter Total (Thousands) Gathering firm reservation fees $ 253,531 $ 566,813 $ 614,356 $ 614,356 $ 614,264 $ 2,647,183 $ 5,310,503 Gathering revenues supported by MVCs 45,877 95,294 100,715 100,715 100,715 309,214 752,530 Transmission firm reservation fees 163,370 334,627 345,527 340,453 336,333 2,478,310 3,998,620 Total $ 462,778 $ 996,734 $ 1,060,598 $ 1,055,524 $ 1,051,312 $ 5,434,707 $ 10,061,653 (a)

Investment in Unconsolidated _2

Investment in Unconsolidated Entity (Tables)	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Unaudited Condensed Financial Statements for the Investment in Unconsolidated Equity	The following tables summarize the unaudited condensed consolidated financial statements of the MVP Joint Venture. Condensed Consolidated Balance Sheets June 30, 2019 December 31, 2018 (Thousands) Current assets $ 836,397 $ 687,657 Non-current assets 4,033,475 3,223,220 Total assets $ 4,869,872 $ 3,910,877 Current liabilities $ 420,534 $ 617,355 Non-current liabilities 2,166 — Equity 4,447,172 3,293,522 Total liabilities and equity $ 4,869,872 $ 3,910,877 Condensed Statements of Consolidated Operations Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Environmental remediation reserve $ 26 $ — $ (2,166 ) $ — Other income 1,785 743 4,698 1,277 Net interest income 23,700 6,989 43,935 12,638 AFUDC — equity 55,298 16,307 102,514 29,489 Net income $ 80,809 $ 24,039 $ 148,981 $ 43,404

Consolidated Variable Interes_2

Consolidated Variable Interest Entities (Tables)	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Consolidated Variable Interest Entity	The following table summarizes EQM's statements of consolidated operations and cash flows, inclusive of transactions with related parties. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (Thousands) Operating revenues $ 406,167 $ 374,697 $ 795,949 $ 745,723 Operating expenses 238,720 128,829 360,488 234,057 Other expenses, net (10,976 ) (11,183 ) (27,059 ) (14,138 ) Net income $ 156,471 $ 234,685 $ 408,402 $ 497,528 Net cash provided by operating activities $ 349,270 $ 338,950 $ 510,243 $ 622,907 Net cash used in investing activities $ (1,324,948 ) $ (1,470,210 ) $ (1,675,305 ) $ (1,756,739 ) Net cash provided by financing activities $ 918,464 $ 1,751,298 $ 1,164,172 $ 1,780,686 The following table presents assets and liabilities included in the Company's consolidated balance sheets that were for the use or obligation of EQM, inclusive of receivables and payables due from or to related parties. June 30, 2019 December 31, 2018 (Thousands) ASSETS Cash and cash equivalents $ 16,625 $ 17,515 Accounts receivable (a) 274,790 254,390 Other current assets 21,971 14,909 Net property, plant and equipment (b) 7,375,142 5,806,628 Investment in unconsolidated entity 2,066,330 1,510,289 Goodwill 1,237,456 1,123,813 Net intangible assets 868,965 576,113 Other assets 201,891 152,464 LIABILITIES Accounts payable (a) $ 179,448 $ 207,877 Capital contribution payable to the MVP Joint Venture 356,223 169,202 Accrued interest 73,443 80,199 Accrued liabilities 38,265 20,672 Credit facility borrowings 1,372,500 625,000 EQM Senior notes 3,459,323 3,456,639 Regulatory and other long-term liabilities 81,093 38,724 (a) Accounts receivable as of June 30, 2019 and December 31, 2018 included $126.7 million and $174.8 million , respectively, of receivables due from EQT. Accounts payable as of December 31, 2018 included approximately $34.0 million of related party accounts payable to EQT. There was no related party balance with EQT included in accounts payable as of June 30, 2019 . (b) Includes approximately $58.6 million conveyed to EQM in the Shared Assets Transaction primarily consisting of IT infrastructure, office equipment, vehicles and office leases. See Note 2 .

Financial Statements (Details)

Financial Statements (Details) - USD ($)	Nov. 12, 2018	May 22, 2018	May 01, 2018	Nov. 13, 2017	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cash distributions paid (as a percent)	80.10%
Limited partner ownership interest (as a percent)							25.00%
Cloud Computing Arrangements
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Hosing arrangement, fixed term (in years)						7 years
Amortization of intangible assets					$ 0	$ 0
EQT Corporation and Subsidiaries
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Limited partner ownership interest (as a percent)	19.90%
Strike Force Midstream Holdings LLC | Strike Force Midstream
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Limited partner ownership interest (as a percent)				75.00%
EQM | Gulfport Transaction
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cash consideration			$ 175,000,000
Limited partner ownership interest (as a percent)			100.00%
EQM | May 2018 Acquisition
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cash consideration		$ 1,150,000,000
Common units (in shares)		5,889,282

Investments in Consolidated, _2

Investments in Consolidated, Non-Wholly-Owed Entities (Details)

Aug. 13, 2019$ / shares

Jul. 24, 2019USD ($)$ / shares

Mar. 31, 2019USD ($)

Mar. 13, 2019USD ($)day$ / sharesshares

Feb. 13, 2019USD ($)shares

Jan. 10, 2019USD ($)$ / sharesshares

Jan. 03, 2019USD ($)shares

Dec. 31, 2018USD ($)

Dec. 31, 2018shares

Jun. 30, 2019USD ($)shares

Mar. 31, 2019USD ($)

Jun. 30, 2018USD ($)

Mar. 31, 2018USD ($)

Jun. 30, 2019USD ($)shares

Jun. 30, 2018USD ($)

Dec. 31, 2018USD ($)

Class of Stock [Line Items]

Purchase of EQGP common units

$ 238,455,000

Results of the EQGP Buyout and the EQM IDR Transaction

$ 1,627,000

(346,543,000)

$ 6,871,000

$ (17,000)

$ 346,500,000

Convertible basis (percentage)

100.00%

Convertible units

$ 30,000,000

Threshold percentage of stock price trigger

140.00%

Threshold trading days | day

20

Threshold amount of stock price trigger

$ 500,000

Threshold consecutive trading days | day

20

Initial purchase price for the shared assets transaction

$ 49,700,000

58,600,000

Cash consideration

8,900,000

482,578,000

$ 382,946,000

Distributions paid to noncontrolling interest unitholders

(189,308,000)

$ (180,745,000)

EQGP | Phantom Share Units (PSUs)

Class of Stock [Line Items]

Units paid in connection with EQGP Buyout (in dollars per share) | $ / shares

$ 20

Units paid in connection with EQGP Buyout (in shares) | shares

29,829

EQM | Subsequent Event

Class of Stock [Line Items]

Cash distributions paid per unit (in dollars per share) | $ / shares

$ 1.160

EQM | Series A Preferred Units | Subsequent Event

Class of Stock [Line Items]

Cash distributions paid per unit (in dollars per share) | $ / shares

$ 0.9339

EQM | Limited Partner Common

Class of Stock [Line Items]

Canceled common units (in shares) | shares

21,811,643

EQM | Limited Partner | Subsequent Event

Class of Stock [Line Items]

Distributions paid to noncontrolling interest unitholders

$ (136,000,000)

Noncontrolling Interests

Class of Stock [Line Items]

Purchase of EQGP common units

$ (244,400,000)

Common Stock

Class of Stock [Line Items]

Purchase of EQGP common units

38,648,000

$ (46,800,000)

Results of the EQGP Buyout and the EQM IDR Transaction

$ 1,627,000

991,098,000

991,100,000

Noncontrolling Interests

Class of Stock [Line Items]

Purchase of EQGP common units

199,807,000

Results of the EQGP Buyout and the EQM IDR Transaction

$ (1,337,641,000)

$ 25,922,000

$ (64,000)

$ 1,300,000,000

EQM | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

117,245,455

117,245,455

Limited partner ownership interest (as a percent)

53.50%

EQM | Common Class B | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

7,000,000

7,000,000

EQM | EQGP | Limited Partner Common

Class of Stock [Line Items]

Partners' capital common units outstanding (in shares) | shares

21,811,643

EQM | Equitrans Gathering Holdings, LLC | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

89,505,616

89,505,616

EQM | Equitrans Gathering Holdings, LLC | Common Class B | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

6,153,907

6,153,907

EQM | EQM GP Corporation | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

89,536

89,536

EQM | EQM GP Corporation | Common Class B | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

6,155

6,155

EQM | Equitrans Midstream Holdings, LLC | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

27,650,303

27,650,303

EQM | Equitrans Midstream Holdings, LLC | Common Class B | Limited Partner Common

Class of Stock [Line Items]

Common units held (in shares) | shares

839,938

839,938

EQM | Public Owned

Class of Stock [Line Items]

Limited partner ownership interest (as a percent)

46.50%

EQGP Unit Purchases

Class of Stock [Line Items]

Aggregate purchase price of EQGP Unit Purchases

$ 16,100,000

$ 291,200,000

EQGP Unit Purchases | EQGP

Class of Stock [Line Items]

Aggregate common units of EQGP Unit Purchases (in shares) | shares

804,140

14,560,281

Limited Call Right

Class of Stock [Line Items]

Aggregate purchase price of EQGP Unit Purchases

$ 221,900,000

Limited Call Right | EQGP

Class of Stock [Line Items]

Aggregate common units of EQGP Unit Purchases (in shares) | shares

11,097,287

IDR Merger Agreement

Class of Stock [Line Items]

Units convertible as of April 1, 2021

$ 2,500,000

Units convertible as of April 1, 2022

2,500,000

Units convertible as of April 1, 2023

$ 2,000,000

IDR Merger Agreement | EQM

Class of Stock [Line Items]

Common units received (in shares) | shares

80,000,000

IDR Merger Agreement | EQM | Common Class B

Class of Stock [Line Items]

Common units received (in shares) | shares

7,000,000

Private Placement | EQM

Class of Stock [Line Items]

Aggregate number of units owned (in shares) | shares

24,605,291

Cash purchase price for Series A Preferred Units (in dollars per share) | $ / shares

$ 48.77

Total gross proceeds for Series A Preferred Units

$ 1,200,000,000

Cash distributions paid per unit (in dollars per share) | $ / shares

$ 1.0364

Cumulative quarterly distribution increasing percentage (A)

2.59%

Cumulative quarterly distribution increasing percentage (B)

1.725%

2019 Acquisitions - Narrative (

2019 Acquisitions - Narrative (Details) $ in Thousands		Apr. 10, 2019USD ($)mi	Mar. 13, 2019USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Business Acquisition [Line Items]
Limited partner ownership interest (as a percent)					25.00%		25.00%
Interest, net of amount capitalized						$ 127,542	$ 33,573
Transaction costs	[1]			$ 15,568	$ 15,741	24,350	31,314
Goodwill				1,347,138		1,347,138		$ 1,239,269
Amortization of intangible assets				13,750	$ 10,387	24,137	$ 20,773
Hornet Midstream Holdings, LLC
Business Acquisition [Line Items]
Length of gathering lines (in miles) | mi		15
Hornet Midstream Holdings, LLC | EQM
Business Acquisition [Line Items]
Limited partner ownership interest (as a percent)		100.00%
Eureka Midstream Holdings, LLC
Business Acquisition [Line Items]
Length of gathering lines (in miles) | mi		190
Eureka Midstream Holdings, LLC | EQM
Business Acquisition [Line Items]
Limited partner ownership interest (as a percent)		60.00%
Bolt-on Acquisition
Business Acquisition [Line Items]
Cash consideration		$ 863,780
Payment of related interest and fees		28,200
Interest, net of amount capitalized		100
Transaction costs				15,200		16,700
Acquisition-related expenses, professional fees				13,500		15,000
Acquisition-related expenses, compensation arrangements				1,700		1,700
Goodwill		107,869
Noncontrolling interests		$ 486,062
Estimated useful life		20 years
Amortization of intangible assets				3,400		3,400
Estimated annual amortization expense, 2019				8,100		8,100
Estimated annual amortization expense, 2020				15,800		15,800
Estimated annual amortization expense, 2021				15,800		15,800
Estimated annual amortization expense, 2022				15,800		15,800
Estimated annual amortization expense, 2023				$ 15,800		$ 15,800
Goodwill, tax deductible amount		$ 23,100
Bolt-on Acquisition | EQM
Business Acquisition [Line Items]
Total consideration			$ 1,030,000
Cash consideration			864,000
Assumed pro-rata debt			$ 167,000
[1]	Operating and maintenance expense charges to EQT of $2.4 million for both the three and six months ended June 30, 2019 . For the three and six months ended June 30, 2018 , operating and maintenance expense included charges from EQT of $12.2 million and $24.4 million , respectively. Selling, general and administrative expense included charges from EQT of $1.0 million for both the three and six months ended June 30, 2019 . Selling, general and administrative expense included charges from EQT of $26.1 million and $50.7 million for the three and six months ended June 30, 2018 , respectively. See Note 8 . Separation and other transaction costs for the three and six months ended June 30, 2018 represents the expenses related to the Rice Merger, the EQM-RMP Mergers and the Drop-Down Transaction (each defined in Note 1 ) and included charges allocated to Equitrans Midstream from EQT of $10.4 million and $26.0 million , respectively. See Notes 1 and 8 .

2019 Acquisitions - Schedule of

2019 Acquisitions - Schedule of Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands	Apr. 10, 2019	Jun. 30, 2019	Dec. 31, 2018
Fair value of assets acquired:
Goodwill		$ 1,347,138	$ 1,239,269
Bolt-on Acquisition
Consideration given:
Cash consideration	$ 861,250
Buyout of Eureka Class B Units and incentive compensation	2,530
Total consideration	863,780
Fair value of liabilities assumed:
Current liabilities	52,458
Long-term debt	300,825
Other long-term liabilities	10,203
Amount attributable to liabilities assumed	363,486
Fair value of assets acquired:
Cash	15,145
Accounts receivable	16,817
Inventory	12,991
Other current assets	882
Net property, plant and equipment	1,222,284
Intangible assets	317,000
Deferred tax asset	5,773
Other assets	14,567
Amount attributable to assets acquired	1,605,459
Noncontrolling interests	(486,062)
Goodwill	$ 107,869

2019 Acquisitions - Schedule _2

2019 Acquisitions - Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination (Details) - Bolt-on Acquisition $ in Thousands	Jun. 30, 2019USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 317,000
Less: accumulated amortization	3,375
Intangible assets, net	$ 313,625

2019 Acquisitions - Schedule _3

2019 Acquisitions - Schedule of Post-Acquisition Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Business Acquisition [Line Items]
Net income attributable to noncontrolling interests	$ 55,959		$ 118,540	$ 199,226	$ 259,555
Net income attributable to Equitrans Midstream	$ 74,521		$ 101,067	$ 130,820	$ 183,796
Bolt-on Acquisition
Business Acquisition [Line Items]
Pro forma operating revenues		$ 28,928
Operating income attributable to Equitrans Midstream		12,496
Net income attributable to noncontrolling interests		4,033
Net income attributable to Equitrans Midstream		$ 6,506

2019 Acquisitions - Schedule _4

2019 Acquisitions - Schedule of Pro Forma Information (Details) - Bolt-on Acquisition - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2018
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma operating revenues	$ 421,362	$ 406,920	$ 803,945
Pro forma net income	208,922	213,071	426,212
Pro forma net income attributable to noncontrolling interests	97,644	89,629	189,036
Pro forma net income attributable to Equitrans Midstream	$ 111,278	$ 123,442	$ 237,176
Pro forma income per share (basic) (in dollars per share)	$ 0.44	$ 0.48	$ 0.93
Pro forma income per share (diluted) (in dollars per share)	$ 0.44	$ 0.48	$ 0.93

Impairment of Long-Lived Asse_2

Impairment of Long-Lived Assets (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Property, Plant and Equipment [Abstract]
Impairment of long-lived assets	[1]	$ 80,135	$ 0	$ 80,135	[2]	$ 0	[2]
[1]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.
[2]	See Note 4 for disclosure regarding impairment of certain of the Company's long-lived assets.

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)lease_agreement	Jun. 30, 2019USD ($)lease_agreement	Apr. 10, 2019USD ($)	Jan. 01, 2019USD ($)
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset	$ 66,400		$ 66,400
Operating lease expenses	3,407		5,340
Cash paid for operating lease liabilities	3,100		5,000
Operating lease liability	67,063		67,063
Operating lease, liability, current	$ 10,700		$ 10,700
Weighted average remaining lease term	9 years		9 years
Weighted average discount rate (percentage)	6.00%		6.00%
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset					$ 49,700
Operating lease liability					$ 49,700
Shared Leases Assignment
Lessee, Lease, Description [Line Items]
Number of lease agreements | lease_agreement		2
Shared Leases Assignment | EQM
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset		$ 33,000
Operating lease liability		$ 33,000
Bolt-on Acquisition
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset				$ 20,000
Operating lease expenses	$ 1,300		$ 1,300
Operating lease liability				$ 20,000
Bolt-on Acquisition | Compressor Lease
Lessee, Lease, Description [Line Items]
Number of lease agreements | lease_agreement			10
Bolt-on Acquisition | Facilities Lease
Lessee, Lease, Description [Line Items]
Number of lease agreements | lease_agreement			1

Leases - Schedule of Operating

Leases - Schedule of Operating Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease cost	$ 3,407	$ 5,340
Short-term lease cost	1,513	1,918
Variable lease cost	69	82
Sublease (income)	(108)	(192)
Total lease cost	$ 4,881	$ 7,148

Leases - Schedule of Operatin_2

Leases - Schedule of Operating Lease Liability Maturities (Details) $ in Thousands	Jun. 30, 2019USD ($)
Leases [Abstract]
2019	$ 6,916
2020	13,237
2021	11,246
2022	9,806
2023	7,747
2024	5,978
Thereafter	30,663
Total	85,593
Less: imputed interest	18,530
Present value of operating lease liability	$ 67,063

Financial Information by Busi_3

Financial Information by Business Segment - Narrative (Details)	6 Months Ended
	Jun. 30, 2019business_linesegment
Segment Reporting [Abstract]
Number of reportable segments | segment	3
Number of lines of business | business_line	3

Financial Information by Busi_4

Financial Information by Business Segment - Schedule of Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Apr. 10, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from external customers (including related parties):
Operating revenues	[1]	$ 406,167		$ 374,697		$ 795,949	$ 745,723
Operating income:
Operating income attributable to Equitrans Midstream		166,175		234,868		426,216	484,208
Reconciliation of operating income to net income:
Equity income	[2]	36,782		10,938		67,845	19,749
Other income		706		944		2,567	1,848
Net interest expense	[3]	61,713		19,884		122,662	31,986
Income tax expense		11,470		7,259		43,920	30,468
Net income		130,480	$ 199,566	219,607	$ 223,744	330,046	443,351
Segment assets:
Total assets		12,436,453				12,436,453			$ 10,523,835
Depreciation:
Total		56,759		42,171		107,270	83,513
Expenditures for segment assets:
Total		278,719		221,421		468,052	376,863
Accrued capital expenditures		103,600	$ 89,700	84,600	$ 75,500	103,600	84,600		109,300	$ 90,700
Gathering
Revenues from external customers (including related parties):
Operating revenues		285,666		241,189		547,547	478,579
Transmission
Revenues from external customers (including related parties):
Operating revenues		92,767		89,145		202,626	196,079
Water
Revenues from external customers (including related parties):
Operating revenues		27,734		44,363		45,776	71,065
Operating segments
Segment assets:
Total assets		11,930,529				11,930,529			9,315,915
Operating segments | Gathering
Revenues from external customers (including related parties):
Operating revenues		285,666		241,189		547,547	478,579
Operating income:
Operating income attributable to Equitrans Midstream		94,131		161,818		276,209	332,853
Segment assets:
Total assets		8,031,401				8,031,401			6,011,654
Depreciation:
Total		37,443		23,882		65,559	46,950
Expenditures for segment assets:
Total		256,318		186,457		414,318	320,595
Operating segments | Transmission
Revenues from external customers (including related parties):
Operating revenues		92,767		89,145		202,626	196,079
Operating income:
Operating income attributable to Equitrans Midstream		63,244		60,642		147,994	140,093
Segment assets:
Total assets		3,636,355				3,636,355			3,066,659
Depreciation:
Total		12,594		12,430		25,127	24,871
Expenditures for segment assets:
Total		11,229		27,962		29,991	46,891
Operating segments | Water
Revenues from external customers (including related parties):
Operating revenues		27,734		44,363		45,776	71,065
Operating income:
Operating income attributable to Equitrans Midstream		10,072		23,408		11,258	38,720
Segment assets:
Total assets		262,773				262,773			237,602
Depreciation:
Total		6,478		5,798		12,894	11,569
Expenditures for segment assets:
Total		8,849		7,002		18,024	9,377
Other/Headquarters, including cash
Operating income:
Operating income attributable to Equitrans Midstream		(1,272)		(11,000)		(9,245)	(27,458)
Segment assets:
Total assets		505,924				505,924			$ 1,207,920
Depreciation:
Total		244		61		3,690	123
Expenditures for segment assets:
Total		2,323		0		5,719	0
Eureka Midstream Holdings, LLC | Operating segments | Gathering
Expenditures for segment assets:
Total		10,900				10,900
Bolt-on Acquisition
Expenditures for segment assets:
Accrued capital expenditures								$ 8,800
MVP Southgate Project | Operating segments | Transmission
Expenditures for segment assets:
Total		$ 156,400		$ 65,800		$ 301,200	$ 182,800
[1]	Operating revenues included related party revenues from EQT Corporation (NYSE: EQT) of $284.0 million and $285.3 million for the three months ended June 30, 2019 and 2018 , respectively, and $568.5 million and $550.9 million for the six months ended June 30, 2019 and 2018 , respectively. See Note 8 .
[2]	Represents equity income from Mountain Valley Pipeline, LLC (the MVP Joint Venture). See Note 9 .
[3]	Net interest expense included interest income on the preferred interest in EQT Energy Supply, LLC (EES) (Preferred Interest) of $1.6 million and $1.7 million for the three months ended June 30, 2019 and 2018 , respectively, and $3.2 million and $3.3 million for the six months ended June 30, 2019 and 2018 , respectively.

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Schedule of Disaggregated Revenue Information, by Business Segment (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Operating revenues	[1]	$ 406,167	$ 374,697	$ 795,949	$ 745,723
Firm reservation fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		229,607	193,924	457,790	401,632
Volumetric-based fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		148,826	136,410	292,383	273,026
Gathering
Disaggregation of Revenue [Line Items]
Operating revenues		285,666	241,189	547,547	478,579
Gathering | Firm reservation fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		147,771	111,702	276,730	221,635
Gathering | Volumetric-based fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		137,895	129,487	270,817	256,944
Transmission
Disaggregation of Revenue [Line Items]
Operating revenues		92,767	89,145	202,626	196,079
Transmission | Firm reservation fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		81,836	82,222	181,060	179,997
Transmission | Volumetric-based fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		10,931	6,923	21,566	16,082
Water
Disaggregation of Revenue [Line Items]
Operating revenues		27,734	44,363	45,776	71,065
Water | Firm reservation fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		0	0	0	0
Water | Volumetric-based fee revenues
Disaggregation of Revenue [Line Items]
Operating revenues		$ 0	$ 0	$ 0	$ 0
[1]	Operating revenues included related party revenues from EQT Corporation (NYSE: EQT) of $284.0 million and $285.3 million for the three months ended June 30, 2019 and 2018 , respectively, and $568.5 million and $550.9 million for the six months ended June 30, 2019 and 2018 , respectively. See Note 8 .

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Summary of Remaining Performance Obligations (Details) $ in Thousands	Jun. 30, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 462,778
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	996,734
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	1,060,598
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	1,055,524
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	1,051,312
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	5,434,707
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	10,061,653
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 163,370
Remaining performance obligations, expected timing	6 months
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 334,627
Remaining performance obligations, expected timing	1 year
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 345,527
Remaining performance obligations, expected timing	1 year
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 340,453
Remaining performance obligations, expected timing	1 year
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 336,333
Remaining performance obligations, expected timing	1 year
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 2,478,310
Transmission firm reservation fees | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 3,998,620
Remaining performance obligations, expected timing
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 253,531
Remaining performance obligations, expected timing	6 months
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 566,813
Remaining performance obligations, expected timing	1 year
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 614,356
Remaining performance obligations, expected timing	1 year
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 614,356
Remaining performance obligations, expected timing	1 year
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 614,264
Remaining performance obligations, expected timing	1 year
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 2,647,183
Gathering firm reservation fees | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 5,310,503
Remaining performance obligations, expected timing
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 45,877
Remaining performance obligations, expected timing	6 months
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 95,294
Remaining performance obligations, expected timing	1 year
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 100,715
Remaining performance obligations, expected timing	1 year
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 100,715
Remaining performance obligations, expected timing	1 year
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 100,715
Remaining performance obligations, expected timing	1 year
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 309,214
Gathering revenues supported by MVCs | Gathering | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total firm reservation fees	$ 752,530
Remaining performance obligations, expected timing

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Narrative (Details)	6 Months Ended
	Jun. 30, 2019
Gathering
Disaggregation of Revenue [Line Items]
Weighted average remaining term	11 years
Transmission
Disaggregation of Revenue [Line Items]
Weighted average remaining term	15 years

Related Party Transactions (Det

Related Party Transactions (Details) - Line of credit - EQGP Working Capital Facility with ETRN - EQGP - USD ($)	2 Months Ended
	Dec. 31, 2018	Nov. 13, 2018
Related Party Transaction [Line Items]
Maximum borrowing capacity		$ 20,000,000
Line of credit outstanding	$ 1,000,000
Maximum outstanding borrowing	3,300,000
Average daily balance of short term loans outstanding	$ 900,000
Weighted average annual interest rate	4.10%

Investment in Unconsolidated _3

Investment in Unconsolidated Entity - Narrative (Details) $ in Thousands	1 Months Ended				6 Months Ended
	Sep. 30, 2019USD ($)	Aug. 31, 2019USD ($)	Jul. 31, 2019USD ($)	May 31, 2019USD ($)	Jun. 30, 2019USD ($)mi	Jun. 30, 2018USD ($)	Jul. 01, 2019USD ($)	Feb. 28, 2019USD ($)	Jan. 31, 2019USD ($)	Apr. 30, 2018mi
Schedule of Equity Method Investments [Line Items]
Capital call notice expected to be paid					$ 301,175	$ 182,805
MVP
Schedule of Equity Method Investments [Line Items]
Length of pipeline (in miles) | mi					300
MVP Southgate Project
Schedule of Equity Method Investments [Line Items]
Length of pipeline (in miles) | mi										70
Variable Interest Entity, Not Primary Beneficiary | MVP
Schedule of Equity Method Investments [Line Items]
Issuance of performance guarantee, remaining capital obligation, percentage									33.00%
Issuance of performance guarantee									$ 261,000
Variable Interest Entity, Not Primary Beneficiary | MVP Southgate Project
Schedule of Equity Method Investments [Line Items]
Issuance of performance guarantee								$ 14,000
Variable Interest Entity, Not Primary Beneficiary | MVP Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest					45.50%
Maximum financial statement exposure					$ 2,004,000
Variable Interest Entity, Not Primary Beneficiary | MVP Southgate Project
Schedule of Equity Method Investments [Line Items]
Ownership interest					47.20%
Capital contribution payable to MVP Joint Venture				$ 4,000
Variable Interest Entity, Not Primary Beneficiary | MVP Southgate Project | Scenario, Forecast
Schedule of Equity Method Investments [Line Items]
Payments to joint venture	$ 1,500	$ 1,600
Variable Interest Entity, Not Primary Beneficiary | MVP Project
Schedule of Equity Method Investments [Line Items]
Capital contribution payable to MVP Joint Venture				$ 352,300
Variable Interest Entity, Not Primary Beneficiary | MVP Project | Scenario, Forecast
Schedule of Equity Method Investments [Line Items]
Payments to joint venture	$ 144,500	$ 114,300
Beneficial Owner | MVP Joint Venture
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest					66.67%
Subsequent Event | Variable Interest Entity, Not Primary Beneficiary | MVP Southgate Project
Schedule of Equity Method Investments [Line Items]
Capital call notice expected to be paid			$ 900
Subsequent Event | Variable Interest Entity, Not Primary Beneficiary | MVP Project
Schedule of Equity Method Investments [Line Items]
Payments to joint venture			$ 93,400
Performance Guarantee | Variable Interest Entity, Not Primary Beneficiary | MVP
Schedule of Equity Method Investments [Line Items]
Guarantor obligations					$ 280,000
Performance Guarantee | Subsequent Event | Variable Interest Entity, Not Primary Beneficiary | MVP
Schedule of Equity Method Investments [Line Items]
Guarantor obligations							$ 249,000

Investment in Unconsolidated _4

Investment in Unconsolidated Entity - Schedule of Unaudited Condensed Financial Statements for the Investment in Unconsolidated Equity (Details) - MVP Joint Venture - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Condensed Consolidated Balance Sheets
Current assets	$ 836,397		$ 836,397		$ 687,657
Non-current assets	4,033,475		4,033,475		3,223,220
Total assets	4,869,872		4,869,872		3,910,877
Current liabilities	420,534		420,534		617,355
Non-current liabilities	2,166		2,166		0
Equity	4,447,172		4,447,172		3,293,522
Total liabilities and equity	4,869,872		4,869,872		$ 3,910,877
Condensed Statements of Consolidated Operations
Environmental remediation reserve	26	$ 0	(2,166)	$ 0
Other income	1,785	743	4,698	1,277
Net interest income	23,700	6,989	43,935	12,638
AFUDC — equity	55,298	16,307	102,514	29,489
Net income	$ 80,809	$ 24,039	$ 148,981	$ 43,404

Debt - Equitrans Midstream Cred

Debt - Equitrans Midstream Credit Facility (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Oct. 31, 2018
Debt Instrument [Line Items]
Letters of credit outstanding	$ 1,372,500,000	$ 1,372,500,000	$ 641,500,000
Equitrans Midstream Credit Facility | Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 100,000,000
Available additional borrowings				200,000,000
Borrowings outstanding	0	0	17,000,000
Maximum amount of short term loans outstanding	13,000,000	44,000,000
Average daily balance of short term loans outstanding	1,000,000	$ 6,000,000
Weighted average annual interest rate (as a percent)		4.20%
Equitrans Midstream Credit Facility | Same-day swing line advances
Debt Instrument [Line Items]
Maximum borrowing capacity				25,000,000
Equitrans Midstream Credit Facility | Letter of credit
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 15,000,000
Letters of credit outstanding	$ 0	$ 0	$ 0

Debt - Equitrans Midstream Term

Debt - Equitrans Midstream Term Loan Facility (Details) - USD ($)	Dec. 31, 2018	Jun. 30, 2019
Debt Instrument [Line Items]
Letters of credit outstanding	$ 641,500,000	$ 1,372,500,000
Term Loans | Equitrans Midstream Term Loans
Debt Instrument [Line Items]
Principal	600,000,000
Net proceeds from offering	568,100,000
Discount	18,000,000
Debt issuance costs	13,900,000
Incremental borrowing capacity		150,000,000
Periodic quarterly payment		6,000,000
Borrowings outstanding	600,000,000	$ 597,000,000
Weighted average annual interest rate (as a percent)		7.00%
Letter of credit | Equitrans Midstream Term Loans
Debt Instrument [Line Items]
Letters of credit outstanding	$ 0	$ 0

Debt - EQGP Working Capital Fac

Debt - EQGP Working Capital Facility with EQT (Details) - EQGP - Line of credit - EQGP Working Capital Facility with EQT - USD ($)	Nov. 12, 2018	Dec. 31, 2018	Jun. 30, 2018	Jun. 30, 2019	Nov. 13, 2018
Short-term Debt [Line Items]
Maximum borrowing capacity					$ 20,000,000
Maximum outstanding borrowing		$ 3,300,000
Weighted average annual interest rate		4.10%
EQT Corporation and Subsidiaries
Short-term Debt [Line Items]
Maximum borrowing capacity				$ 50,000,000
Maximum amount of short term loans outstanding	$ 3,200,000
Maximum outstanding borrowing			$ 200,000
Weighted average annual interest rate			3.20%

Debt - EQM Revolving Credit Fac

Debt - EQM Revolving Credit Facility (Details)	1 Months Ended	3 Months Ended		6 Months Ended
	Oct. 31, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)	Nov. 01, 2018USD ($)
Debt Instrument [Line Items]
Letters of credit outstanding		$ 1,372,500,000		$ 1,372,500,000		$ 641,500,000
EQM Credit Facility | EQM | Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding		1,100,000,000		1,100,000,000		625,000,000
Letters of credit outstanding		$ 1,000,000		$ 1,000,000		$ 1,000,000
Weighted average annual interest rate (as a percent)		3.80%	3.40%	3.90%	3.20%
EQM Credit Facility | Line of credit | EQM
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000						$ 3,000,000,000
Additional available borrowings	750,000,000
Maximum amount of short term loans outstanding			$ 338,000,000	$ 1,200,000,000	$ 420,000,000
Average daily balance of short term loans outstanding		$ 1,043,000,000	$ 122,000,000	$ 993,000,000	$ 211,000,000
EQM Credit Facility | Same-day swing line advances | EQM
Debt Instrument [Line Items]
Maximum borrowing capacity	250,000,000
EQM Credit Facility | Letter of credit | EQM
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000,000
Three Billion Credit Facility | Line of credit
Debt Instrument [Line Items]
Consolidated leverage ratio		5		5
Consolidated leverage ratio under certain circumstances		5.50		5.50

Debt - Eureka Credit Facility (

Debt - Eureka Credit Facility (Details) - Eureka Midstream, LLC - Line of credit - Eureka Credit Facility	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Oct. 31, 2018USD ($)
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 400,000,000
Additional available borrowings	$ 100,000,000
Available additional borrowings	$ 500,000,000	$ 500,000,000	$ 500,000,000
Maximum consolidated leverage ratio	4.75	4.75	4.75
Maximum consolidated leverage ratio for certain measurement periods following certain acquisitions	5.25	5.25	5.25
Consolidated interest ratio requirement	2.50	2.50	2.50
Borrowings outstanding	$ 293,000,000	$ 293,000,000	$ 293,000,000
Maximum amount of short term loans outstanding		293,000,000
Average daily balance of short term loans outstanding		$ 277,000,000
Weighted average annual interest rate (as a percent)			4.50%
Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Eurodollar | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			1.75%
Eurodollar | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
Federal Funds Effective Rate
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			0.75%
Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate			2.00%

Debt - EQM Term Loan Facility (

Debt - EQM Term Loan Facility (Details) - $2.5 Billion Senior Notes - EQM - Line of credit - USD ($)	Jun. 25, 2018	Apr. 25, 2018	Jun. 25, 2018	Jun. 30, 2018
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 2,500,000,000		$ 2,500,000,000
Line of credit expiration period		364 days
Debt issuance costs	$ 3,000,000
Maximum amount of short term loans outstanding			$ 1,825,000,000
Average daily balance of short term loans outstanding			$ 1,231,000,000
Weighted average annual interest rate (as a percent)			3.30%

Debt - RMP Credit Facility (Det

Debt - RMP Credit Facility (Details) - USD ($)	Jul. 23, 2018	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Repayments of debt			$ 670,500,000	$ 2,596,500,000
RMP Credit Facility | Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 850,000,000
Repayments of debt	$ 260,000,000
Maximum amount of short term loans outstanding		$ 325,000,000		336,000,000
Average daily balance of short term loans outstanding		$ 305,000,000		$ 306,000,000
Weighted average annual interest rate (as a percent)		3.90%		3.80%

Debt - EQM 4.125% and 4.00% Sen

Debt - EQM 4.125% and 4.00% Senior Notes (Details) - EQM - EQM Senior notes - USD ($)	Jun. 30, 2019	Dec. 31, 2016	Sep. 30, 2014
EQM 4.125% Senior Notes due 2026
Debt Instrument [Line Items]
Interest rate (as a percent)	4.125%	4.125%
Principal		$ 500,000,000
EQM 4.00% Senior Notes due 2024
Debt Instrument [Line Items]
Interest rate (as a percent)	4.00%		4.00%
Principal			$ 500,000,000

Debt - EQM $2.5 Billion Senior

Debt - EQM $2.5 Billion Senior Notes (Details) - USD ($)	1 Months Ended
	Jun. 30, 2018	Jul. 23, 2018	Apr. 25, 2018
RMP Credit Facility | Credit facility borrowings
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 850,000,000
EQM | EQM Senior notes
Debt Instrument [Line Items]
Net proceeds from offering	$ 2,465,800,000
Discount	11,800,000
Debt issuance costs	22,400,000
EQM | $2.5 Billion Senior Notes | Credit facility borrowings
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 2,500,000,000		$ 2,500,000,000
EQM | EQM 4.75% Senior Notes due 2023 | EQM Senior notes
Debt Instrument [Line Items]
Interest rate (as a percent)	4.75%
Principal	$ 1,100,000,000
EQM | EQM 5.50% Senior Notes due 2028 | EQM Senior notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
Principal	$ 850,000,000
EQM | EQM 6.50% Senior Notes due 2048 | EQM Senior notes
Debt Instrument [Line Items]
Interest rate (as a percent)	6.50%
Principal	$ 550,000,000

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
EQM | Level 3 | Fair Value | EES
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred interest	$ 127	$ 122
EQM | Level 3 | Carrying Value | EES
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred interest	112	115
EQM Senior notes | EQM | Fair Value, Measurements, Recurring | Level 2 | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	3,612	3,425
EQM Senior notes | EQM | Fair Value, Measurements, Recurring | Level 2 | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	3,459	3,457
Equitrans Midstream Term Loans | Term Loans | Level 2 | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	604	590
Equitrans Midstream Term Loans | Term Loans | Level 2 | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 568	$ 568.2

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($)	Nov. 12, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Class of Stock [Line Items]
Common stock outstanding (in shares)		$ 254,691,255		$ 254,691,255
Issuance of Equitrans Midstream common stock (in shares)	254,268,864
Potentially dilutive securities (in shares)		49,458	601,622	50,167	601,622
EQT Corporation and Subsidiaries | The Separation and Distribution Agreement
Class of Stock [Line Items]
Common stock outstanding (in shares)	$ 254,586,700
Equitrans Midstream | EQT Corporation and Subsidiaries
Class of Stock [Line Items]
Common stock outstanding (in shares)		$ 50,599,503		$ 50,599,503

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Effective tax rate	8.10%	3.20%	11.70%	6.40%

Consolidated Variable Interes_3

Consolidated Variable Interest Entities (Details) - USD ($)	Mar. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Variable Interest Entity [Line Items]
Initial purchase price for the shared assets transaction	$ 49,700,000			$ 58,600,000
Operating revenues		$ 406,167,000	$ 374,697,000	795,949,000	$ 745,723,000
Operating expenses		238,720,000	128,829,000	360,488,000	234,057,000
Other expenses, net		(10,976,000)	(11,183,000)	(27,059,000)	(14,138,000)
Net income		156,471,000	234,685,000	408,402,000	497,528,000
Net cash provided by operating activities		349,270,000	338,950,000	510,243,000	622,907,000
Net cash used in investing activities		(1,324,948,000)	(1,470,210,000)	(1,675,305,000)	(1,756,739,000)
Net cash provided by financing activities		918,464,000	$ 1,751,298,000	1,164,172,000	$ 1,780,686,000
Cash and cash equivalents
Variable Interest Entity [Line Items]
ASSETS		16,625,000		16,625,000		$ 17,515,000
Accounts receivable
Variable Interest Entity [Line Items]
ASSETS		274,790,000		274,790,000		254,390,000
Other current assets
Variable Interest Entity [Line Items]
ASSETS		21,971,000		21,971,000		14,909,000
Net property, plant and equipment
Variable Interest Entity [Line Items]
ASSETS		7,375,142,000		7,375,142,000		5,806,628,000
Investment in unconsolidated entity
Variable Interest Entity [Line Items]
ASSETS		2,066,330,000		2,066,330,000		1,510,289,000
Goodwill
Variable Interest Entity [Line Items]
ASSETS		1,237,456,000		1,237,456,000		1,123,813,000
Net intangible assets
Variable Interest Entity [Line Items]
ASSETS		868,965,000		868,965,000		576,113,000
Other assets
Variable Interest Entity [Line Items]
ASSETS		201,891,000		201,891,000		152,464,000
Accounts payable
Variable Interest Entity [Line Items]
LIABILITIES		179,448,000		179,448,000		207,877,000
Capital contribution payable to the MVP Joint Venture
Variable Interest Entity [Line Items]
LIABILITIES		356,223,000		356,223,000		169,202,000
Accrued interest
Variable Interest Entity [Line Items]
LIABILITIES		73,443,000		73,443,000		80,199,000
Accrued liabilities
Variable Interest Entity [Line Items]
LIABILITIES		38,265,000		38,265,000		20,672,000
Credit facility borrowings
Variable Interest Entity [Line Items]
LIABILITIES		1,372,500,000		1,372,500,000		625,000,000
EQM Senior notes
Variable Interest Entity [Line Items]
LIABILITIES		3,459,323,000		3,459,323,000		3,456,639,000
Regulatory and other long-term liabilities
Variable Interest Entity [Line Items]
LIABILITIES		81,093,000		81,093,000		38,724,000
EES | Accounts receivable
Variable Interest Entity [Line Items]
ASSETS		126,700,000		126,700,000		174,800,000
EES | Accounts payable
Variable Interest Entity [Line Items]
LIABILITIES		$ 0		$ 0		$ 34,000,000