0001564590-21-024987 | 10-Q | XBRL Viewer

May 04, 2020

May 14, 2020

Distribution Made To Limited Partner [Line Items]

$ 0.4310

Second Quarter 2020

Aug. 06, 2020

Aug. 14, 2020

Distribution Made To Limited Partner [Line Items]

$ 0.4363

Third Quarter 2020

Nov. 05, 2020

Nov. 13, 2020

Distribution Made To Limited Partner [Line Items]

$ 0.4417

Fourth Quarter 2020

Feb. 04, 2021

Feb. 12, 2021

Distribution Made To Limited Partner [Line Items]

$ 0.4471

First Quarter 2021

May 03, 2021

^[1]

May 13, 2021

^[1]

$ 0.4526

^[1]

[1]	For more information, see Note 14, Subsequent Events.

Segments

3 Months Ended

Mar. 31, 2021

Segment Reporting [Abstract]

Segments

Note 13. Segments

Our operations are located in the United States and are organized into three reportable segments: (1) gathering, (2) processing and storage and (3) terminaling and export. Our reportable segments comprise the structure used by our Chief Operating Decision Maker (“CODM”) to make key operating decisions and assess performance. These segments are strategic business units with differing products and services. Our CODM evaluates the segments’ operating performance based on multiple measures including Adjusted EBITDA, defined as net income (loss) before net interest expense, income tax expense (benefit), depreciation and amortization and our proportional share of depreciation of equity affiliates, as further adjusted to eliminate the impact of certain items that we do not consider indicative of our ongoing operating performance, such as transaction costs, other income and other non-cash, non‑recurring items, if applicable.

The following tables reflect certain financial data for each reportable segment:

	Gathering		Processing and Storage		Terminaling and Export		Interest and Other			Consolidated
(in millions)
For the Three Months Ended March 31, 2021
Revenues and other income	$	152.7	$	103.5	$	32.6	$	-		$	288.8
Net income (loss)		92.4		70.9		24.0		(27.7	)		159.6
Net income (loss) attributable to Hess Midstream LP		6.4		4.8		1.6		(4.2	)		8.6
Depreciation expense		24.9		11.2		4.1		-			40.2
Proportional share of equity affiliates' depreciation		-		1.3		-		-			1.3
Income from equity investments		-		2.7		-		-			2.7
Interest expense, net		-		-		-		23.1			23.1
Income tax expense		-		-		-		2.5			2.5
Adjusted EBITDA		117.3		83.4		28.1		(2.1	)		226.7
Capital expenditures*		19.4		3.7		-		-			23.1

	Gathering		Processing and Storage		Terminaling and Export		Interest and Other			Consolidated
(in millions)
For the Three Months Ended March 31, 2020
Revenues and other income	$	141.6	$	97.0	$	52.2	$	-		$	290.8
Net income (loss)		75.9		62.7		20.7		(30.3	)		129.0
Net income (loss) attributable to Hess Midstream LP		4.8		4.0		1.3		(3.6	)		6.5
Depreciation expense		23.3		11.2		4.0		-			38.5
Proportional share of equity affiliates' depreciation		-		1.3		-		-			1.3
Income from equity investments		-		2.7		-		-			2.7
Interest expense, net		-		-		-		24.8			24.8
Income tax expense		-		-		-		1.7			1.7
Adjusted EBITDA		99.2		75.2		24.7		(3.8	)		195.3
Capital expenditures*		15.8		41.1		0.1		-			57.0

*Includes acquisition, expansion and maintenance capital expenditures, as applicable.

Total assets for the reportable segments are as follows:


	March 31, 2021		December 31, 2020
(in millions)
Gathering	$	1,859.3	$	1,856.2
Processing and Storage⁽¹⁾		1,161.6		1,170.3
Terminaling and Export		290.0		292.3
Interest and Other		77.7		55.7
Total assets	$	3,388.6	$	3,374.5

(1)	Includes investment in equity investees of $103.6 million as of March 31, 2021 and $108.4 million as of December 31, 2020.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Subsequent Events - Additional Information (Detail) - $ / shares		3 Months Ended
	Apr. 23, 2021	Mar. 31, 2021	Mar. 31, 2020
Subsequent Event [Line Items]
Distributions to unitholders - per unit/share		$ 0.4471	$ 0.4258
Subsequent Event \| Class A Shares
Subsequent Event [Line Items]
Quarterly cash distribution declared date	Apr. 23, 2021
Quarterly cash distribution declared per Class A share	$ 0.4526
Distribution made to limited partner, increase in percentage than prior year quarter declared	1.20%
Distribution made to limited partner, increase in percentage on an annualized basis	5.00%
Distribution payable date	May 13, 2021
Record Date	May 03, 2021
Subsequent Event \| Class B Shares
Subsequent Event [Line Items]
Distributions to unitholders - per unit/share	$ 0.4526
Units representing noncontrolling limited partner interests	259,516,928

Related Party Transactions - Summary of Classification of Charges between Operating and Maintenance Expenses and General and Administrative Expenses (Detail) - Hess - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Operating and maintenance expenses	$ 15.7	$ 15.5
General and administrative expenses	4.2	3.8
Total	$ 19.9	$ 19.3

Equity-Based Compensation

3 Months Ended

Mar. 31, 2021

Equity-Based Compensation

Note 9. Equity‑Based Compensation

Equity‑based award activity for the three months ended March 31, 2021 is as follows:

				Weighted Average
				Award Date
	Number of Shares			Fair Value
Outstanding and unvested shares at December 31, 2020		228,344		$	13.78
Granted		78,347			22.40
Vested		(110,109	)		14.91
Outstanding and unvested shares at March 31, 2021		196,582		$	16.58

As of March 31, 2021, $3.0 million of compensation cost related to unvested restricted shares awarded under our long-term incentive plan remains to be recognized over an expected weighted‑average period of 2.3 years.

Related Party Transactions - Summary of Revenues From Contracts With Customers on Disaggregated Basis (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Total revenues from contracts with customers	$ 288.8	$ 290.6
Other income		0.2
Total revenues	288.8	290.8
Oil and Gas Gathering Services
Disaggregation Of Revenue [Line Items]
Total revenues from contracts with customers	128.7	117.4
Processing and Storage Services
Disaggregation Of Revenue [Line Items]
Total revenues from contracts with customers	103.5	96.8
Terminaling and Export Services
Disaggregation Of Revenue [Line Items]
Total revenues from contracts with customers	32.6	52.2
Water Gathering and Disposal Services
Disaggregation Of Revenue [Line Items]
Total revenues from contracts with customers	$ 24.0	$ 24.2

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Accrued Liabilities Current [Abstract]

Accrued Liabilities

3 Months Ended

Mar. 31, 2021

Accrued Liabilities

Note 6. Accrued Liabilities

Accrued liabilities are as follows:

	March 31, 2021		December 31, 2020
(in millions)
Accrued interest	$	13.9	$	18.0
Accrued capital expenditures		10.5		13.6
Other accruals		15.8		22.5
Total	$	40.2	$	54.1

Earnings per Share (Tables)

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Schedule of Earnings per Share

We calculate earnings per Class A Share as we do not have any other participating securities. Substantially all of income tax expense is attributed to earnings of Class A Shares reflective of our organizational structure. Class B Units of the Partnership together with the equal number of Class B Shares of the Company are convertible to Class A Shares of the Company on a one-for-one basis. In addition, our restricted equity-based awards may have a dilutive effect on our earnings per share. Diluted earnings per Class A Share are calculated using the “treasury stock method” or “if-converted method”, whichever is more dilutive.

	Three Months Ended March 31,
(in millions, except per share amounts)	2021		2020
Net income	$	159.6	$	129.0
Less: Net income attributable to noncontrolling interest		151.0		122.5
Net income attributable to Hess Midstream LP		8.6		6.5
Net income attributable to Hess Midstream LP per Class A share:
Basic:	$	0.45	$	0.37
Diluted:	$	0.43	$	0.35
Weighted average Class A shares outstanding:
Basic:		19.3		18.0
Diluted:		19.4		18.0

Earnings per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Dilutive Restricted Shares
Limited Partners Capital Account [Line Items]
Weighted average number shares	122,222	52,442
Hess and GIP \| Class A Shares
Limited Partners Capital Account [Line Items]
Conversion of Class B units and Class B shares into Class A shares	100.00%

Equity Offering

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

Equity Offering

Note 3. Equity Offering

On March 15, 2021, the Sponsors completed an underwritten public equity offering of 6,900,000 of our Class A shares, inclusive of the underwriters’ option to purchase up to 900,000 of additional shares, at a price of $21.00 per Class A share, less underwriting discounts. The Sponsors received net proceeds from the offering of $139.9 million, after deducting underwriting discounts; we did not receive any proceeds in the offering. The offering was conducted pursuant to a registration rights agreement among us and the Sponsors. The Class A Shares sold in the offering were obtained by the Sponsors by exchanging to us 6,900,000 of their Class B Units in the Partnership, together with an equal number of our Class B Shares. As a result of the exchange, Hess Midstream LP’s consolidated ownership in the Partnership increased from 6.3% at December 31, 2020 to 8.8% at March 31, 2021. Hess Midstream LP retained control in the Partnership based on the delegation of control provisions, as described above in Note 2, Basis of Presentation. As a result of the transaction, we recognized an adjustment to the carrying amount of noncontrolling interest and Class A shareholders’ capital balance of $31.8 million to reflect the change in ownership interest. In addition, we recognized an additional deferred tax asset of $26.4 million for the temporary differences related to the change between carrying amount and tax basis of our investment in the Partnership. The effect of recognizing the additional deferred tax asset was included in Class A shareholders’ equity balance in the accompanying consolidated statement of changes in partners’ capital due to the transaction being characterized as a transaction among or with shareholders.

Description of Business - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021 Segment
Description Of Business [Line Items]
Number of reportable segments	3
Hess
Description Of Business [Line Items]
Percentage of ownership in joint venture	50.00%
GIP II Blue Holding Partnership, L.P
Description Of Business [Line Items]
Percentage of ownership in joint venture	50.00%

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%
Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%
Hess
Related Party Transaction [Line Items]
MVC shortfall fee payments	$ 13.4	$ 1.0
Percentage of ownership in joint venture	50.00%
Hess \| Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%
Hess \| Amended and Restated Commercial Agreement
Related Party Transaction [Line Items]
Minimum volume commitments, Description	Minimum volume commitments (“MVCs”) are equal to 80% of Hess’ nominations in each development plan that apply on a three-year rolling basis such that MVCs are set for the three years following the most recent nomination. Without our consent, the MVCs resulting from the nominated volumes for any quarter or year contained in any prior development plan shall not be reduced by any updated development plan unless dedicated production is released by us. The applicable MVCs may, however, be increased as a result of the nominations contained in any such updated development plan.
Minimum volume commitments expressed as percentage of related party nominations in development plans	80.00%
Initial term of agreement	10 years
Agreement description	each of our commercial agreements with Hess has an initial 10-year term effective January 1, 2014 (“Initial Term”).
Number of rights to extend the term of agreement	one
Advance period to call for extension of term of agreement	3 years
Secondary term of agreement	10 years
Hess \| Amended and Restated Agreement for Certain Gas Gathering Sub-system
Related Party Transaction [Line Items]
Initial term of agreement	15 years
Agreement description	For this gathering sub-system, the Initial Term is 15 years effective January 1, 2014 and for the water services agreements the Initial Term is 14 years effective January 1, 2019.
Secondary term of agreement	5 years
Hess \| Amended and Restated Water Services Agreements
Related Party Transaction [Line Items]
Initial term of agreement	14 years
Secondary term of agreement	10 years
Hess \| Terminal and Export Services Agreement
Related Party Transaction [Line Items]
Commercial agreement period	20 years
Hess \| Commercial Agreements Other Than Storage Services Agreement and Terminal and Export Services Agreement
Related Party Transaction [Line Items]
Minimum volume commitments, Description	During the Secondary Term of our commercial agreements, Hess will continue to have MVCs equal to 80% of Hess’ nominations in each development plan that apply on a three-year rolling basis through the Secondary Term.
Minimum volume commitments expressed as percentage of related party nominations in development plans	80.00%
Maximum consumer price index percentage	3.00%
Fee recalculation model description	the fee recalculation model under each applicable agreement will be replaced by an inflation-based fee structure. The initial fee for the first year of the Secondary Term will be determined based on the average fees paid by Hess under the applicable agreement during the last three years of the Initial Term (with such fees adjusted for inflation through the first year of the Secondary Term). For each year following the first year of the Secondary Term, the applicable fee will be adjusted annually based on the percentage change in the consumer price index, provided that we may not increase any fee by more than 3% in any calendar year solely by reason of an increase in the consumer price index, and no fee will ever be reduced below the amount of the applicable fee payable by Hess in the prior year as a result of a decrease in the consumer price index.
Targa Resources Corp. \| LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%

Partners' Capital and Distributions (Tables)

3 Months Ended

Mar. 31, 2021

Partners Capital Notes [Abstract]

Schedule of Distributions Declared and Paid

The following table details the distributions declared and/or paid for the periods presented:

Period	Record Date	Distribution Date	Distribution per Class A share
First Quarter 2020	May 4, 2020	May 14, 2020	$	0.4310
Second Quarter 2020	August 6, 2020	August 14, 2020	$	0.4363
Third Quarter 2020	November 5, 2020	November 13, 2020	$	0.4417
Fourth Quarter 2020	February 4, 2021	February 12, 2021	$	0.4471
First Quarter 2021⁽¹⁾	May 3, 2021	May 13, 2021	$	0.4526

⁽¹⁾ For more information, see Note 14, Subsequent Events.

Basis of Presentation

3 Months Ended

Mar. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Basis of Presentation

Note 2. Basis of Presentation

Subsequent Events

3 Months Ended

Mar. 31, 2021

Subsequent Events [Abstract]

Subsequent Events

Note 14. Subsequent Events

On April 23, 2021, the board of directors of our general partner declared a quarterly cash distribution of $0.4526 per Class A share for the quarter ended March 31, 2021, a 1.2% increase compared to the distribution on the Class A shares for the quarter ended December 31, 2020, which equals a 5% increase on an annualized basis. The distribution will be payable on May 13, 2021, to shareholders of record as of the close of business on May 3, 2021. Simultaneously, the Partnership will make a distribution of $0.4526 per Class B unit of the Partnership to the Sponsors as holders of an aggregate of 259,516,928 Class B units of the Partnership.

Related Party Transactions - Summary of Activity Related to Agreements with Related Party (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Earnings from equity investments	$ 2.7	$ 2.7
Distributions received from equity investments	7.5
LM4
Related Party Transaction [Line Items]
Processing fee incurred	6.9	6.4
Earnings from equity investments	2.7	$ 2.7
Distributions received from equity investments	$ 7.5

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 1.5	$ 2.6
Accounts receivable—affiliate:
From contracts with customers	108.1	93.2
Other current assets	4.2	5.6
Total current assets	113.8	101.4
Equity investments	103.6	108.4
Property, plant and equipment, net	3,094.5	3,111.3
Long-term receivable—affiliate	0.9	0.9
Deferred tax asset	66.4	42.5
Other noncurrent assets	9.4	10.0
Total assets	3,388.6	3,374.5
Liabilities
Accounts payable—trade	20.3	30.0
Accounts payable—affiliate	18.6	21.0
Accrued liabilities	40.2	54.1
Current maturities of long-term debt	12.5	10.0
Other current liabilities	2.7	9.9
Total current liabilities	94.3	125.0
Long-term debt	1,886.2	1,900.1
Other noncurrent liabilities	23.0	23.4
Total liabilities	2,003.5	2,048.5
Partners' capital
Total partners' capital	184.0	125.0
Noncontrolling interest	1,201.1	1,201.0
Total partners' capital	1,385.1	1,326.0
Total liabilities and partners' capital	3,388.6	3,374.5
Class A Shares
Partners' capital
Common unitholders	184.0	125.0
Total partners' capital	$ 184.0	$ 125.0

Property, Plant and Equipment - Components of Property, Plant and Equipment (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 4,186.0	$ 4,162.7
Accumulated depreciation	(1,091.5)	(1,051.4)
Property, plant and equipment, net	3,094.5	3,111.3
Logistics Facilities and Railcars
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 386.5	386.2
Logistics Facilities and Railcars \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	20 years
Logistics Facilities and Railcars \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Storage Facilities
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 19.5	19.5
Storage Facilities \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	20 years
Storage Facilities \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Other
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 22.1	20.9
Other \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	20 years
Other \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Construction-In-Progress
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 232.6	227.3
Gathering Assets \| Pipelines
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	22 years
Total property, plant and equipment, at cost	$ 1,478.7	1,470.6
Gathering Assets \| Compressors, Pumping Stations and Terminals
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 786.7	778.6
Gathering Assets \| Compressors, Pumping Stations and Terminals \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	22 years
Gathering Assets \| Compressors, Pumping Stations and Terminals \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Gas Plant Assets \| Pipelines, Pipes and Valves
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 460.0	460.0
Gas Plant Assets \| Pipelines, Pipes and Valves \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	22 years
Gas Plant Assets \| Pipelines, Pipes and Valves \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Gas Plant Assets \| Equipment
Property Plant And Equipment [Line Items]
Total property, plant and equipment, at cost	$ 428.3	428.3
Gas Plant Assets \| Equipment \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	12 years
Gas Plant Assets \| Equipment \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	30 years
Gas Plant Assets \| Buildings
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	35 years
Total property, plant and equipment, at cost	$ 182.3	182.3
Gas Plant Assets \| Processing and Fractionation Facilities
Property Plant And Equipment [Line Items]
Property, plant and equipment, Estimated useful life	25 years
Total property, plant and equipment, at cost	$ 189.3	$ 189.0

Equity Offering - Additional Information (Detail) - USD ($)	Mar. 15, 2021	Dec. 31, 2020	Mar. 31, 2021
Class Of Stock [Line Items]
Percentage of ownership interest	8.80%	6.30%
Class A Shares
Class Of Stock [Line Items]
Underwritten public equity offering	6,900,000
Shares issued, price per share	$ 21.00
Proceeds from Issuance of public equity offering	$ 0
Net proceeds received by sponsors from public equity offering	139,900,000
Common unitholders	31,800,000	$ 125,000,000.0	$ 184,000,000.0
Additions to deferred tax asset	$ 26,400,000
Class A Shares \| Maximum
Class Of Stock [Line Items]
Underwriters’ option to purchase additional shares	900,000
Class B Shares
Class Of Stock [Line Items]
Underwritten public equity offering	6,900,000

Segments - Total Assets for Reportable Segments (Detail) - USD ($)
$ in Millions

Mar. 31, 2021

Dec. 31, 2020

$ 3,388.6

$ 3,374.5

Interest and Other

Gathering Opco | Operating Segments

77.7

55.7

Processing and Storage | Operating Segments

1,859.3

1,856.2

Terminaling and Export | Operating Segments

^[1]

1,161.6

1,170.3

$ 290.0

$ 292.3

[1]	Includes investment in equity investees of $103.6 million as of March 31, 2021 and $108.4 million as of December 31, 2020.

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies

Note 12. Commitments and Contingencies

Environmental Contingencies

The Company is subject to federal, state and local laws and regulations relating to the environment. As of March 31, 2021, our reserves for estimated remediation liabilities included in Accrued liabilities and Other noncurrent liabilities were $0.8 million and $3.1 million, respectively, compared with $0.9 million and $3.1 million, respectively, as of December 31, 2020.

Legal Proceedings

In the ordinary course of business, the Company is from time to time party to various judicial and administrative proceedings. We regularly assess the need for accounting recognition or disclosure of these contingencies. In the case of a known contingency, we accrue a liability when the loss is probable and the amount is reasonably estimable. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum of the range is accrued.

As of March 31, 2021 and December 31, 2020, we did not have material accrued liabilities for legal contingencies. Based on currently available information, we believe it is remote that the outcome of known matters would have a material adverse impact on our financial condition, results of operations or cash flows.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 159.6	$ 129.0
Other comprehensive income
Effect of hedge (gains) losses reclassified to income		(0.2)
Total other comprehensive income		(0.2)
Comprehensive income	159.6	128.8
Less: Comprehensive income (loss) attributable to noncontrolling interest	151.0	122.3
Comprehensive income attributable to Hess Midstream LP	$ 8.6	$ 6.5

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Property Plant And Equipment [Abstract]

Partners' Capital and Distributions - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021
Partners Capital Notes [Abstract]
Period of cash distribution to shareholders	45 days

CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Mar. 31, 2021	Dec. 31, 2020
Class A Shares
Common units issued	25,038,417	18,028,308
Common units outstanding	25,038,417	18,028,308
Class B Shares
Common units issued	259,516,928	266,416,928
Common units outstanding	259,516,928	266,416,928

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Trading Symbol	HESM
Entity Registrant Name	Hess Midstream LP
Entity Central Index Key	0001789832
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	001-39163
Entity Tax Identification Number	84-3211812
Entity Address, Address Line One	1501 McKinney Street
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77010
City Area Code	713
Local Phone Number	496-4200
Entity Common Stock, Shares Outstanding		25,038,417
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Class A shares representing limited partner interests
Security Exchange Name	NYSE
Entity Interactive Data Current	Yes

Segments - Additional Information (Detail)	3 Months Ended
Segments - Additional Information (Detail)	Mar. 31, 2021 Segment
Segment Reporting [Abstract]
Number of reportable segments	3

Property, Plant and Equipment

3 Months Ended

Mar. 31, 2021

Property, Plant and Equipment

Note 5. Property, Plant and Equipment

Property, plant and equipment, at cost, is as follows:

	Estimated useful lives	March 31, 2021			December 31, 2020
(in millions, except for number of years)
Gathering assets
Pipelines	22 years	$	1,478.7		$	1,470.6
Compressors, pumping stations and terminals	22 to 25 years		786.7			778.6
Gas plant assets
Pipelines, pipes and valves	22 to 25 years		460.0			460.0
Equipment	12 to 30 years		428.3			428.3
Buildings	35 years		182.3			182.3
Processing and fractionation facilities	25 years		189.3			189.0
Logistics facilities and railcars	20 to 25 years		386.5			386.2
Storage facilities	20 to 25 years		19.5			19.5
Other	20 to 25 years		22.1			20.9
Construction-in-progress	N/A		232.6			227.3
Total property, plant and equipment, at cost			4,186.0			4,162.7
Accumulated depreciation			(1,091.5	)		(1,051.4	)
Property, plant and equipment, net		$	3,094.5		$	3,111.3

Segments (Tables)

3 Months Ended

Mar. 31, 2021

Segment Reporting [Abstract]

Financial Data for Each Reportable Segment

The following tables reflect certain financial data for each reportable segment:

	Gathering		Processing and Storage		Terminaling and Export		Interest and Other			Consolidated
(in millions)
For the Three Months Ended March 31, 2021
Revenues and other income	$	152.7	$	103.5	$	32.6	$	-		$	288.8
Net income (loss)		92.4		70.9		24.0		(27.7	)		159.6
Net income (loss) attributable to Hess Midstream LP		6.4		4.8		1.6		(4.2	)		8.6
Depreciation expense		24.9		11.2		4.1		-			40.2
Proportional share of equity affiliates' depreciation		-		1.3		-		-			1.3
Income from equity investments		-		2.7		-		-			2.7
Interest expense, net		-		-		-		23.1			23.1
Income tax expense		-		-		-		2.5			2.5
Adjusted EBITDA		117.3		83.4		28.1		(2.1	)		226.7
Capital expenditures*		19.4		3.7		-		-			23.1

	Gathering		Processing and Storage		Terminaling and Export		Interest and Other			Consolidated
(in millions)
For the Three Months Ended March 31, 2020
Revenues and other income	$	141.6	$	97.0	$	52.2	$	-		$	290.8
Net income (loss)		75.9		62.7		20.7		(30.3	)		129.0
Net income (loss) attributable to Hess Midstream LP		4.8		4.0		1.3		(3.6	)		6.5
Depreciation expense		23.3		11.2		4.0		-			38.5
Proportional share of equity affiliates' depreciation		-		1.3		-		-			1.3
Income from equity investments		-		2.7		-		-			2.7
Interest expense, net		-		-		-		24.8			24.8
Income tax expense		-		-		-		1.7			1.7
Adjusted EBITDA		99.2		75.2		24.7		(3.8	)		195.3
Capital expenditures*		15.8		41.1		0.1		-			57.0

*Includes acquisition, expansion and maintenance capital expenditures, as applicable.

Total Assets for Reportable Segments

Total assets for the reportable segments are as follows:


	March 31, 2021		December 31, 2020
(in millions)
Gathering	$	1,859.3	$	1,856.2
Processing and Storage⁽¹⁾		1,161.6		1,170.3
Terminaling and Export		290.0		292.3
Interest and Other		77.7		55.7
Total assets	$	3,388.6	$	3,374.5

(1)	Includes investment in equity investees of $103.6 million as of March 31, 2021 and $108.4 million as of December 31, 2020.

Partners' Capital and Distributions

3 Months Ended

Mar. 31, 2021

Partners Capital Notes [Abstract]

Partners' Capital and Distributions

Note 8. Partners’ Capital and Distributions

Our partnership agreement requires that, within 45 days after the end of each quarter, we distribute all of our available cash, as defined in the partnership agreement, to shareholders of record on the applicable record date. The following table details the distributions declared and/or paid for the periods presented:

Period	Record Date	Distribution Date	Distribution per Class A share
First Quarter 2020	May 4, 2020	May 14, 2020	$	0.4310
Second Quarter 2020	August 6, 2020	August 14, 2020	$	0.4363
Third Quarter 2020	November 5, 2020	November 13, 2020	$	0.4417
Fourth Quarter 2020	February 4, 2021	February 12, 2021	$	0.4471
First Quarter 2021⁽¹⁾	May 3, 2021	May 13, 2021	$	0.4526

⁽¹⁾ For more information, see Note 14, Subsequent Events.

Segments - Financial Data for Each Reportable Segment (Detail) - USD ($)
$ in Millions

3 Months Ended

Mar. 31, 2021

Mar. 31, 2020

$ 288.8

$ 290.8

Net income (loss) attributable to Hess Midstream LP

159.6

129.0

8.6

6.5

Proportional share of equity affiliates' depreciation

40.2

38.5

1.3

Income from equity investments

2.7

Interest expense, net

23.1

24.8

Income tax expense

2.5

1.7

226.7

195.3

^[1]

23.1

57.0

Interest and Other

Net income (loss) attributable to Hess Midstream LP

(27.7)

(30.3)

(4.2)

(3.6)

Interest expense, net

23.1

24.8

Income tax expense

2.5

1.7

Gathering Opco | Operating Segments

(2.1)

(3.8)

152.7

141.6

Net income (loss) attributable to Hess Midstream LP

92.4

75.9

6.4

4.8

24.9

23.3

117.3

99.2

Processing and Storage | Operating Segments

^[1]

19.4

15.8

103.5

97.0

Net income (loss) attributable to Hess Midstream LP

70.9

62.7

4.8

4.0

Proportional share of equity affiliates' depreciation

11.2

1.3

Income from equity investments

2.7

83.4

75.2

Terminaling and Export | Operating Segments

^[1]

3.7

41.1

32.6

52.2

Net income (loss) attributable to Hess Midstream LP

24.0

20.7

1.6

1.3

4.1

4.0

$ 28.1

24.7

Accrued Liabilities Current [Abstract]

^[1]

$ 0.1

[1]	Includes acquisition, expansion and maintenance capital expenditures, as applicable

Accrued Liabilities (Tables)

3 Months Ended

Mar. 31, 2021

Schedule of Accrued Liabilities

Accrued liabilities are as follows:

	March 31, 2021		December 31, 2020
(in millions)
Accrued interest	$	13.9	$	18.0
Accrued capital expenditures		10.5		13.6
Other accruals		15.8		22.5
Total	$	40.2	$	54.1

Concentration of Credit Risk

3 Months Ended

Mar. 31, 2021

Risks And Uncertainties [Abstract]

Concentration of Credit Risk

Note 11. Concentration of Credit Risk

Hess represented approximately 100% of our total revenues and accounts receivable for the three months ended March 31, 2021 and 2020.

Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2021

Property Plant And Equipment [Abstract]

Components of Property, Plant and Equipment

Property, plant and equipment, at cost, is as follows:

	Estimated useful lives	March 31, 2021			December 31, 2020
(in millions, except for number of years)
Gathering assets
Pipelines	22 years	$	1,478.7		$	1,470.6
Compressors, pumping stations and terminals	22 to 25 years		786.7			778.6
Gas plant assets
Pipelines, pipes and valves	22 to 25 years		460.0			460.0
Equipment	12 to 30 years		428.3			428.3
Buildings	35 years		182.3			182.3
Processing and fractionation facilities	25 years		189.3			189.0
Logistics facilities and railcars	20 to 25 years		386.5			386.2
Storage facilities	20 to 25 years		19.5			19.5
Other	20 to 25 years		22.1			20.9
Construction-in-progress	N/A		232.6			227.3
Total property, plant and equipment, at cost			4,186.0			4,162.7
Accumulated depreciation			(1,091.5	)		(1,051.4	)
Property, plant and equipment, net		$	3,094.5		$	3,111.3

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues
Affiliate services	$ 288.8	$ 290.6
Type of Revenue [Extensible List]	hesm:AffiliateServicesMember	hesm:AffiliateServicesMember
Other income		$ 0.2
Total revenues	$ 288.8	290.8
Costs and expenses
Operating and maintenance expenses (exclusive of depreciation shown separately below)	59.8	91.9
Depreciation expense	40.2	38.5
General and administrative expenses	6.3	7.6
Total costs and expenses	106.3	138.0
Income from operations	182.5	152.8
Income from equity investments	2.7	2.7
Interest expense, net	23.1	24.8
Income before income tax expense	162.1	130.7
Income tax expense	2.5	1.7
Net income	159.6	129.0
Less: Net income attributable to noncontrolling interest	151.0	122.5
Net income attributable to Hess Midstream LP	8.6	6.5
Class A Shares
Costs and expenses
Net income	$ 8.6	$ 6.5
Net income attributable to Hess Midstream LP per Class A share:
Net income attributable to Hess Midstream LP per Class A share, Basic	$ 0.45	$ 0.37
Net income attributable to Hess Midstream LP per Class A share, Diluted	$ 0.43	$ 0.35
Weighted average Class A shares outstanding
Weighted average Class A shares outstanding subsequent to the restructuring, Basic	19.3	18.0
Weighted average Class A shares outstanding subsequent to the restructuring, Diluted	19.4	18.0

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL (UNAUDITED) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Partners Capital [Abstract]
Distributions to unitholders - per share	$ 0.4471	$ 0.4258

Concentration of Credit Risk - Additional Information (Detail) - Credit Concentration Risk	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	100.00%
Revenue
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	100.00%

Debt and Interest Expense - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021 USD ($)
Debt Instrument [Line Items]
Debt covenant, leverage ratio	550.00%
Ratio of debt to EBITDA	500.00%
Secured leverage ratio - Maximum	400.00%
Debt instrument covenant, description	The Credit Facilities contain representations and warranties, affirmative and negative covenants and events of default that the Partnership considers to be customary for an agreement of this type, including a covenant that requires the Partnership to maintain a ratio of total debt to EBITDA (as defined in the Credit Facilities) for the prior four fiscal quarters of not greater than 5.00 to 1.00 as of the last day of each fiscal quarter (5.50 to 1.00 during the specified period following certain acquisitions) and, prior to the Partnership obtaining an investment grade credit rating, a ratio of secured debt to EBITDA for the prior four fiscal quarters of not greater than 4.00 to 1.00 as of the last day of each fiscal quarter.
Carrying Value
Debt Instrument [Line Items]
Total debt	$ 1,898,700,000
Level 2
Debt Instrument [Line Items]
Total debt fair value	$ 1,949,300,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility - Term	5 years
Maximum borrowing capacity	$ 1,000,000,000.0
Borrowings	$ 174,000,000.0
Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Interest rate applicable margin	1.55%
Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Interest rate applicable margin	2.50%
Term Loan A Facility
Debt Instrument [Line Items]
Credit facility - Term	5 years
Maximum borrowing capacity	$ 400,000,000.0
Borrowings	$ 397,500,000
Syndicated Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility - Term	5 years
Syndicated Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Interest rate applicable margin	1.275%
Syndicated Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Interest rate applicable margin	2.00%
Fixed-Rate Senior Notes
Debt Instrument [Line Items]
Debt covenant, leverage ratio	425.00%
5.625% Fixed Rate Senior Notes due 2026
Debt Instrument [Line Items]
Fixed-rate senior notes	$ 800,000,000.0
5.625% Fixed Rate Senior Notes due 2026 \| Fixed-Rate Senior Notes
Debt Instrument [Line Items]
Debt instrument interest rate	5.625%
Debt instrument due year	2026
Frequency of periodic interest payment	semi‑annually
Interest payment terms	Interest is payable semi‑annually on February 15 and August 15.
5.125% Fixed Rate Senior Notes due 2028
Debt Instrument [Line Items]
Fixed-rate senior notes	$ 550,000,000.0
5.125% Fixed Rate Senior Notes due 2028 \| Fixed-Rate Senior Notes
Debt Instrument [Line Items]
Debt instrument interest rate	5.125%
Debt instrument due year	2028
Frequency of periodic interest payment	semi‑annually
Interest payment terms	Interest is payable semi‑annually on June 15 and December 15.

Segments - Total Assets for Reportable Segments (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2019
Processing and Storage
Segment Reporting Information [Line Items]
Cash contributed to acquire equity investments	$ 103.6	$ 108.4

Related Party Transactions

3 Months Ended

Mar. 31, 2021

Related Party Transactions

Note 4. Related Party Transactions

Commercial Agreements

Effective January 1, 2014, we entered into long-term fee-based (i) gas gathering, (ii) crude oil gathering, (iii) gas processing and fractionation, (iv) storage services, and (v) terminal and export services agreements with certain subsidiaries of Hess. Effective January 1, 2019, we entered into long-term fee-based water services agreements with a subsidiary of Hess. For the services performed under these commercial agreements, we receive a fee per barrel of crude oil, barrel of water, Mcf of natural gas, or Mcf equivalent of NGLs, as applicable, delivered during each month, and Hess is obligated to provide us with minimum volumes of crude oil, water, natural gas and NGLs. Minimum volume commitments (“MVCs”) are equal to 80% of Hess’ nominations in each development plan that apply on a three-year rolling basis such that MVCs are set for the three years following the most recent nomination. Without our consent, the MVCs resulting from the nominated volumes for any quarter or year contained in any prior development plan shall not be reduced by any updated development plan unless dedicated production is released by us. The applicable MVCs may, however, be increased as a result of the nominations contained in any such updated development plan.

Except for the water services agreements and except for a certain gathering sub-system as described below, each of our commercial agreements with Hess has an initial 10-year term effective January 1, 2014 (“Initial Term”). For this gathering sub-system, the Initial Term is 15 years effective January 1, 2014 and for the water services agreements the Initial Term is 14 years effective January 1, 2019. Each of our commercial agreements other than our storage services agreement includes an inflation escalator and a fee recalculation mechanism that allows fees to be adjusted annually during the Initial Term for updated estimates of cumulative throughput volumes and our capital and operating expenditures in order to target a return on capital deployed over the Initial Term of the applicable commercial agreement (or, with respect to the crude oil services fee under our terminal and export services agreement, the 20-year period commencing on the effective date of the agreement).

We have the unilateral right, exercisable by the delivery of a written notice on or before the date that is three years prior to the expiration of the Initial Term, to extend each commercial agreement for one additional 10-year term (“Secondary Term”). For a certain gathering sub-system, the Secondary Term is 5-years and for the water services agreements the Secondary Term is 10 years. On December 30, 2020, we exercised our renewal options to extend the terms of certain crude oil gathering, terminaling, storage, gas processing and gas gathering commercial agreements with Hess for the Secondary Term through December 31, 2033. There were no changes to any provisions of the existing commercial agreements as a result of the exercise of the renewal options. For the remaining water gathering and disposal agreements as well as the remaining gas gathering agreement, we have the sole option to renew these agreements for an additional term that is exercisable at a later date.

During the Secondary Term of each of our commercial agreements other than our storage services agreement and terminal and export services agreement (with respect to crude oil terminaling services), the fee recalculation model under each applicable agreement will be replaced by an inflation-based fee structure. The initial fee for the first year of the Secondary Term will be determined based on the average fees paid by Hess under the applicable agreement during the last three years of the Initial Term (with such fees adjusted for inflation through the first year of the Secondary Term). For each year following the first year of the Secondary Term, the applicable fee will be adjusted annually based on the percentage change in the consumer price index, provided that we may not increase any fee by more than 3% in any calendar year solely by reason of an increase in the consumer price index, and no fee will ever be reduced below the amount of the applicable fee payable by Hess in the prior year as a result of a decrease in the consumer price index. During the Secondary Term of our commercial agreements, Hess will continue to have MVCs equal to 80% of Hess’ nominations in each development plan that apply on a three-year rolling basis through the Secondary Term.

For the three months ended March 31, 2021 and 2020, approximately 100% of our revenues were attributable to our fee‑based commercial agreements with Hess, including revenues from third‑party volumes contracted with Hess and delivered to us under these agreements. We retain control of our assets and the flow of volumes based on available capacity within our integrated gathering, processing and terminaling systems. Together with Hess, we are pursuing strategic relationships with third‑party producers and other midstream companies with operations in the Bakken in order to maximize our utilization rates.

Revenues from contracts with customers on a disaggregated basis are as follows:

	Three Months Ended March 31,
	2021		2020
(in millions)
Oil and gas gathering services	$	128.7	$	117.4
Processing and storage services		103.5		96.8
Terminaling and export services		32.6		52.2
Water gathering and disposal services		24.0		24.2
Total revenues from contracts with customers	$	288.8	$	290.6
Other income		-		0.2
Total revenues	$	288.8	$	290.8

During the three months ended March 31, 2021 and 2020, we earned $13.4 million and $1.0 million, respectively, of MVC shortfall fee payments.

The following table presents third-party pass-through costs for which we recognize revenues in an amount equal to the costs. These third-party costs are included in Operating and maintenance expenses in the accompanying unaudited consolidated statements of operations.

	Three Months Ended March 31,
	2021		2020
(in millions)
Produced water trucking and disposal costs	$	9.4	$	16.6
Electricity fees		9.3		9.5
Rail transportation costs		0.1		23.2
Total	$	18.8	$	49.3

Omnibus and Employee Secondment Agreements

Under our omnibus and employee secondment agreements, Hess provides substantial operational and administrative services to us in support of our assets and operations. For the three months ended March 31, 2021 and 2020, we had the following charges from Hess. The classification of these charges between operating and maintenance expenses and general and administrative expenses is based on the fundamental nature of the services being performed for our operations.

	Three Months Ended March 31,
	2021		2020
(in millions)
Operating and maintenance expenses	$	15.7	$	15.5
General and administrative expenses		4.2		3.8
Total	$	19.9	$	19.3

LM4 Agreements

Separately from our commercial agreements with Hess, we entered into a gas processing agreement with Little Missouri 4 (“LM4”), a 50/50 joint venture with Targa Resources Corp., under which we pay a processing fee per Mcf of natural gas and reimburse LM4 for our proportionate share of electricity costs. These processing fees are included in Operating and maintenance expenses in the accompanying consolidated statements of operations. In addition, we share profits and losses and receive distributions from LM4 under the LM4 amended and restated limited liability company agreement based on our ownership interest. For the three months ended March 31, 2021 and 2020, we had the following activity related to our agreements with LM4:

	Three Months Ended March 31,
	2021		2020
(in millions)
Processing fee incurred	$	6.9	$	6.4
Earnings from equity investments		2.7		2.7
Distributions received from equity investments		7.5		-

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net income	$ 159.6	$ 129.0
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation expense	40.2	38.5
(Gain) loss on interest rate swaps		(0.2)
(Income) loss from equity investments	(2.7)	(2.7)
Distributions from equity investments	7.5
Amortization of deferred financing costs	1.7	1.8
Equity-based compensation expense	0.4	0.5
Deferred income tax expense (benefit)	2.5	1.7
Changes in assets and liabilities:
Accounts receivable – affiliate	(14.9)	(19.1)
Other current and noncurrent assets	1.4	1.2
Accounts payable – trade	(9.7)	7.3
Accounts payable – affiliate	(1.9)	(2.8)
Accrued liabilities	(10.8)	(9.2)
Other current and noncurrent liabilities	(7.9)	(5.8)
Net cash provided by (used in) operating activities	165.4	140.2
Cash flows from investing activities
Additions to property, plant and equipment	(26.7)	(78.1)
Net cash provided by (used in) investing activities	(26.7)	(78.1)
Cash flows from financing activities
Net proceeds from (repayments of) bank borrowings with maturities of 90 days or less	(10.0)	60.0
Bank borrowings with maturities of greater than 90 days
Repayments	(2.5)
Financing costs		(1.3)
Distributions to shareholders	(8.2)	(7.6)
Distributions to noncontrolling interest	(119.1)	(113.4)
Net cash provided by (used in) financing activities	(139.8)	(62.3)
Increase (decrease) in cash and cash equivalents	(1.1)	(0.2)
Cash and cash equivalents, beginning of period	2.6	3.3
Cash and cash equivalents, end of period	1.5	3.1
Supplemental disclosure of non-cash investing and financing activities:
(Increase) decrease in accrued capital expenditures and related liabilities	3.6	$ 21.1
Recognition of deferred tax asset	$ 26.4

Debt and Interest Expense

3 Months Ended

Mar. 31, 2021

Debt Disclosure [Abstract]

Debt and Interest Expense

Note 7. Debt and Interest Expense

Fixed‑Rate Senior Notes

As of March 31, 2021, the Partnership had $800.0 million of 5.625% fixed‑rate senior notes due 2026 that were issued to qualified institutional investors. The notes are guaranteed by certain subsidiaries of the Partnership. Interest is payable semi‑annually on February 15 and August 15.

In addition, as of March 31, 2021, the Partnership had $550.0 million of 5.125% fixed‑rate senior notes due 2028 that were issued to qualified institutional investors. The notes are guaranteed by certain subsidiaries of the Partnership. Interest is payable semi‑annually on June 15 and December 15.

Each of the indentures for the 2026 and 2028 senior notes contains customary covenants that restrict our ability and the ability of our restricted subsidiaries to (i) declare or pay any dividend or make any other restricted payments; (ii) transfer or sell assets or subsidiary stock; (iii) incur additional debt; or (iv) make restricted investments, unless, at the time of and immediately after giving pro forma effect to such restricted payments and any related incurrence of indebtedness or other transactions, no default has occurred and is continuing or would occur as a consequence of such restricted payment and if the leverage ratio does not exceed 4.25 to 1.00. As of March 31, 2021, we were in compliance with all debt covenants under the indentures.

In addition, the covenants included in the indentures governing the senior notes contain provisions that allow the Company to satisfy the Partnership’s reporting obligations under the indenture, as long as any such financial information of the Company contains information reasonably sufficient to identify the material differences, if any, between the financial information of the Company, on the one hand, and the Partnership and its subsidiaries on a stand-alone basis, on the other hand and the Company does not directly own capital stock of any person other than the Partnership and its subsidiaries, or material business operations that would not be consolidated with the financial results of the Partnership and its subsidiaries. The Company is a holding company and has no independent assets or operations. Other than the interest in the Partnership and the effect of federal and state income taxes that are recognized at the Company level, there are no material differences between the consolidated financial statements of the Partnership and the consolidated financial statements of the Company.

Credit Facilities

As of March 31, 2021, the Partnership had senior secured credit facilities (the “Credit Facilities”) consisting of a $1,000.0 million 5-year revolving credit facility and a fully drawn $400.0 million 5-year Term Loan A facility. Facility fees accrue on the total capacity of the revolving credit facility. Borrowings under the 5-year Term Loan A facility will generally bear interest at LIBOR plus the applicable margin ranging from 1.55% to 2.50%, while the applicable margin for the 5-year syndicated revolving credit facility ranges from 1.275% to 2.000%. Pricing levels for the facility fee and interest-rate margins are based on the Partnership’s ratio of total debt to EBITDA (as defined in the Credit Facilities). If the Partnership obtains an investment grade credit rating, the pricing levels will be based on the Partnership’s credit ratings in effect from time to time. At March 31, 2021, borrowings of $174.0 million were drawn and outstanding under the Partnership’s revolving credit facility, and borrowings of $397.5 million, excluding deferred issuance costs, were drawn and outstanding under the Partnership’s Term Loan A facility.

The Credit Facilities can be used for borrowings and letters of credit for general corporate purposes. The Credit Facilities are guaranteed by each direct and indirect wholly owned material domestic subsidiary of the Partnership, and are secured by first priority perfected liens on substantially all of the presently owned and after-acquired assets of the Partnership and its direct and indirect wholly owned material domestic subsidiaries, including equity interests directly owned by such entities, subject to certain customary exclusions. The Credit Facilities contain representations and warranties, affirmative and negative covenants and events of default that the Partnership considers to be customary for an agreement of this type, including a covenant that requires the Partnership to maintain a ratio of total debt to EBITDA (as defined in the Credit Facilities) for the prior four fiscal quarters of not greater than 5.00 to 1.00 as of the last day of each fiscal quarter (5.50 to 1.00 during the specified period following certain acquisitions) and, prior to the Partnership obtaining an investment grade credit rating, a ratio of secured debt to EBITDA for the prior four fiscal quarters of not greater than 4.00 to 1.00 as of the last day of each fiscal quarter. As of March 31, 2021, the Partnership was in compliance with these financial covenants.

Fair Value Measurement

At March 31, 2021, our total debt had a carrying value of $1,898.7 million and had a fair value of approximately $1,949.3 million, based on Level 2 inputs in the fair value measurement hierarchy. The carrying value of the amounts under the Term Loan A facility and revolving credit facility at March 31, 2021, approximated their fair value. Any changes in interest rates do not impact cash outflows associated with fixed rate interest payments or settlement of debt principal, unless a debt instrument is repurchased prior to maturity.

Description of Business

3 Months Ended

Mar. 31, 2021

Description Of Business [Abstract]

Description of Business

Note 1. Description of Business

Hess Midstream LP (“the Company”) is a fee-based, growth-oriented, Delaware limited partnership that operates, develops and acquires a diverse set of midstream assets and provides fee-based services to Hess Corporation (“Hess”) and third-party customers. We are managed and controlled by Hess Midstream GP LLC, the general partner of our general partner that is owned 50/50 by Hess and GIP II Blue Holding Partnership, L.P. (“GIP” and together with Hess, the “Sponsors”).

Our assets are primarily located in the Bakken and Three Forks shale plays in the Williston Basin area of North Dakota, which we collectively refer to as the Bakken. Our assets and operations are organized into the following three reportable segments: (1) gathering, (2) processing and storage and (3) terminaling and export (see Note 13, Segments).

Unless the context otherwise requires, references in this report to the “Company,” “we,” “our,” “us” or like terms, refer to Hess Midstream LP and its subsidiaries.

Accrued Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Accrued Liabilities Current [Abstract]
Accrued interest	$ 13.9	$ 18.0
Accrued capital expenditures	10.5	13.6
Other accruals	15.8	22.5
Total	$ 40.2	$ 54.1

Commitments and Contingencies - Additional Information (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Estimated remediation liabilities included in accrued liabilities	$ 800,000	$ 900,000
Estimated remediation liabilities included in other noncurrent liabilities	3,100,000	3,100,000
Accrued liabilities for legal contingencies	$ 0	$ 0

CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL (UNAUDITED) - USD ($) $ in Millions	Total	Class A Shares	Noncontrolling Interest	Accumulated Other Comprehensive Income
Balance, beginning of period at Dec. 31, 2019	$ 1,332.1	$ 131.1	$ 1,200.6	$ 0.4
Net income	129.0	6.5	122.5
Equity-based compensation	0.5	0.5
Distributions to unitholders	(121.0)	(7.6)	(113.4)
Other comprehensive income (loss)	(0.2)			(0.2)
Balance, end of period at Mar. 31, 2020	1,340.4	130.5	1,209.7	$ 0.2
Balance, beginning of period at Dec. 31, 2020	1,326.0	125.0	1,201.0
Net income	159.6	8.6	151.0
Equity-based compensation	0.4	0.4
Distributions to unitholders	(127.3)	(8.2)	(119.1)
Recognition of deferred tax asset	26.4	26.4
Sales of shares held by Sponsors		31.8	(31.8)
Balance, end of period at Mar. 31, 2021	$ 1,385.1	$ 184.0	$ 1,201.1

Amount after tax and reclassification adjustments of other comprehensive income (loss).

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Equity-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Schedule of Equity-based Award Activity

Equity‑based award activity for the three months ended March 31, 2021 is as follows:

				Weighted Average
				Award Date
	Number of Shares			Fair Value
Outstanding and unvested shares at December 31, 2020		228,344		$	13.78
Granted		78,347			22.40
Vested		(110,109	)		14.91
Outstanding and unvested shares at March 31, 2021		196,582		$	16.58

Related Party Transactions (Tables)

3 Months Ended

Mar. 31, 2021

Summary of Revenues From Contracts With Customers on Disaggregated Basis

Revenues from contracts with customers on a disaggregated basis are as follows:

	Three Months Ended March 31,
	2021		2020
(in millions)
Oil and gas gathering services	$	128.7	$	117.4
Processing and storage services		103.5		96.8
Terminaling and export services		32.6		52.2
Water gathering and disposal services		24.0		24.2
Total revenues from contracts with customers	$	288.8	$	290.6
Other income		-		0.2
Total revenues	$	288.8	$	290.8

Summary of Third-party Pass-through Costs for Which Revenues in Amount Equal to Costs are Recognized and Classification of Charges between Operating and Maintenance Expenses and General and Administrative Expenses

	Three Months Ended March 31,
	2021		2020
(in millions)
Produced water trucking and disposal costs	$	9.4	$	16.6
Electricity fees		9.3		9.5
Rail transportation costs		0.1		23.2
Total	$	18.8	$	49.3

For the three months ended March 31, 2021 and 2020, we had the following charges from Hess. The classification of these charges between operating and maintenance expenses and general and administrative expenses is based on the fundamental nature of the services being performed for our operations.

	Three Months Ended March 31,
	2021		2020
(in millions)
Operating and maintenance expenses	$	15.7	$	15.5
General and administrative expenses		4.2		3.8
Total	$	19.9	$	19.3

Summary of Activity Related to Agreements with Related Party

For the three months ended March 31, 2021 and 2020, we had the following activity related to our agreements with LM4:

	Three Months Ended March 31,
	2021		2020
(in millions)
Processing fee incurred	$	6.9	$	6.4
Earnings from equity investments		2.7		2.7
Distributions received from equity investments		7.5		-

Equity-Based Compensation - Schedule of Equity-based Award Activity (Detail) - Restricted Share	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding and unvested shares at December 31, 2020, Number of Shares \| shares	228,344
Granted, Number of Shares \| shares	78,347
Vested, Number of Shares \| shares	(110,109)
Outstanding and unvested shares at March 31, 2021, Number of Shares \| shares	196,582
Outstanding and unvested shares at December 31, 2020, Weighted Average Award Date Fair Value \| $ / shares	$ 13.78
Granted, Weighted Average Award Date Fair Value \| $ / shares	22.40
Vested, Weighted Average Award Date Fair Value \| $ / shares	14.91
Outstanding and unvested shares at March 31 2021, Weighted Average Award Date Fair Value \| $ / shares	$ 16.58

Equity-Based Compensation - Additional Information (Detail) - 2017 Long-Term Incentive Plan $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cost related to restricted shares to be recognized	$ 3.0
Cost related to unvested restricted shares to be recognized, over an expected weighted-average period	2 years 3 months 18 days

Earnings per Share

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Earnings per Share

Note 10. Earnings per Share

	Three Months Ended March 31,
(in millions, except per share amounts)	2021		2020
Net income	$	159.6	$	129.0
Less: Net income attributable to noncontrolling interest		151.0		122.5
Net income attributable to Hess Midstream LP		8.6		6.5
Net income attributable to Hess Midstream LP per Class A share:
Basic:	$	0.45	$	0.37
Diluted:	$	0.43	$	0.35
Weighted average Class A shares outstanding:
Basic:		19.3		18.0
Diluted:		19.4		18.0

For the three months ended March 31, 2021 and 2020 the weighted average number of Class A shares outstanding included 122,222 and 52,442 dilutive restricted shares, respectively.

Basis of Presentation - Additional Information (Detail)	3 Months Ended	12 Months Ended
Basis of Presentation - Additional Information (Detail)	Mar. 31, 2021	Dec. 31, 2020
Hess and GIP
Accounting Policies [Line Items]
Noncontrolling interest percentage	91.20%	93.70%

Related Party Transactions - Summary of Third-party Pass-through Costs for Which Revenues in Amount Equal to Costs are Recognized (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Reimbursement revenue	$ 288.8	$ 290.6
Hess
Related Party Transaction [Line Items]
Total	18.8	49.3
Hess \| Produced Water Trucking and Disposal Costs
Related Party Transaction [Line Items]
Reimbursement revenue	9.4	16.6
Hess \| Electricity Fees
Related Party Transaction [Line Items]
Reimbursement revenue	9.3	9.5
Hess \| Rail Transportation Costs
Related Party Transaction [Line Items]
Reimbursement revenue	$ 0.1	$ 23.2