XML 44 R33.htm IDEA: XBRL DOCUMENT
v3.21.2

Equity Offering - Additional Information (Detail) - USD ($) |  |  | 6 Months Ended
--- | --- | --- | ---
Mar. 15, 2021 | Dec. 31, 2020 | Jun. 30, 2021
Class Of Stock [Line Items] |  |  |
Percentage of ownership interest |  | 6.30% | 8.80%
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 |  |

X
- Definition Limited liability company LLC or limited partnership LP managing member or general partner ownership controlling interest. + References No definition available. + Details
Name: | hesm_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipControllingInterest
Namespace Prefix: | hesm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Net proceeds received by sponsors from public equity offering. + References No definition available. + Details
Name: | hesm_NetProceedsReceivedBySponsorsFromPublicEquityOffering
Namespace Prefix: | hesm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Underwriters’ option to purchase additional shares. + References No definition available. + Details
Name: | hesm_UnderwritersOptionToPurchaseAdditionalShares
Namespace Prefix: | hesm_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Underwritten public equity offering. + References No definition available. + Details
Name: | hesm_UnderwrittenPublicEquityOffering
Namespace Prefix: | hesm_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
Name: | us-gaap_DeferredTaxAssetsGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of the limited partners' ownership interests. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770 + Details
Name: | us-gaap_LimitedPartnersCapitalAccount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOrSaleOfEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Per share or per unit amount of equity securities issued. + References No definition available. + Details
Name: | us-gaap_SharesIssuedPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |