Debt instrument maturity year.

No definition available.

Name:	hesm_DebtInstrumentMaturityYear
Namespace Prefix:	hesm_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Leverage ratio.

+ References

No definition available.

+ Details

Name:	hesm_LeverageRatio
Namespace Prefix:	hesm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility Expiration Period Year

+ References

No definition available.

+ Details

Name:	hesm_LineOfCreditFacilityExpirationPeriodYear
Namespace Prefix:	hesm_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Secured leverage ratio.

+ References

No definition available.

+ Details

Name:	hesm_SecuredLeverageRatio
Namespace Prefix:	hesm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

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

- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

+ Details

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

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

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

- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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+ Details

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

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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+ Details

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

- Definition

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

+ References

+ Details

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

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

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

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details

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

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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Debt and Interest Expense - Additional Information (Detail) - USD ($)		6 Months Ended
	Mar. 05, 2025	Jun. 30, 2025	Feb. 12, 2025
Carrying Value
Debt Instrument [Line Items]
Total debt		$ 3,714,400,000
Level 2
Debt Instrument [Line Items]
Total debt fair value		$ 3,752,200,000
Credit Facility
Debt Instrument [Line Items]
Credit facility - maturity year		2027
Maximum borrowing capacity		$ 1,400,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Debt covenant, leverage ratio		500.00%
Credit facility - Term		5 years
Maximum borrowing capacity		$ 1,000,000,000
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 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 (the “Secured Debt Financial Covenant”).
Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Interest rate applicable margin		1.375%
Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Interest rate applicable margin		2.05%
Revolving Credit Facility \| Midstream
Debt Instrument [Line Items]
Borrowings		$ 273,000,000
Term Loan A Facility
Debt Instrument [Line Items]
Credit facility - Term		5 years
Maximum borrowing capacity		$ 400,000,000
Term Loan A Facility \| Minimum
Debt Instrument [Line Items]
Interest rate applicable margin		1.65%
Term Loan A Facility \| Maximum
Debt Instrument [Line Items]
Interest rate applicable margin		2.55%
Term Loan A Facility \| Midstream
Debt Instrument [Line Items]
Borrowings		$ 375,000,000
Following Acquisitions \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt covenant, leverage ratio		550.00%
Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt covenant, leverage ratio		425.00%
6.500% Fixed Rate Senior Unsecured Notes due 2029
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes		$ 600,000,000
6.500% Fixed Rate Senior Unsecured Notes due 2029 \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		6.50%
Debt instrument due year		2029
Frequency of periodic interest payment		semi‑annually
Interest payment terms		Interest is payable semi‑annually on June 1 and December 1.
5.875 Fixed Rate Senior Unsecured Notes due 2028
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes		$ 800,000,000	$ 800,000,000
5.875 Fixed Rate Senior Unsecured Notes due 2028 \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		5.875%	5.875%
Debt instrument due year		2028
Frequency of periodic interest payment		semi‑annually
Interest payment terms		Interest is payable semi‑annually on March 1 and September 1
5.500% Fixed Rate Senior Unsecured Notes due 2030
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes		$ 400,000,000
5.500% Fixed Rate Senior Unsecured Notes due 2030 \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		5.50%
Debt instrument due year		2030
Frequency of periodic interest payment		semi‑annually
Interest payment terms		Interest is payable semi‑annually on April 15 and October 15.
4.250% Fixed Rate Senior Unsecured Notes due 2030
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes		$ 750,000,000
4.250% Fixed Rate Senior Unsecured Notes due 2030 \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		4.25%
Debt instrument due year		2030
Frequency of periodic interest payment		semi‑annually
Interest payment terms		Interest is payable semi‑annually on February 15 and August 15.
5.625% Fixed Rate Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes	$ 800,000,000
5.625% Fixed Rate Senior Unsecured Notes due 2026 \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.625%
Debt instrument due year		2026
Recognized extinguishment loss	$ 2,000,000
5.125% Fixed Rate Senior Unsecured Notes due 2028
Debt Instrument [Line Items]
Aggregate principal amount of fixed-rate senior notes		$ 550,000,000.0
5.125% Fixed Rate Senior Unsecured Notes due 2028 \| Unsecured Debt [Member]
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.