Time charter revenues and related contract balances - Direct financing lease receivable and unguaranteed residual value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing lease
Minimum lease payments	$ 589,074	$ 589,074
Unguaranteed residual value	146,000	146,000
Unearned income	(440,345)	(440,345)
Initial direct cost, net	3,095	3,095
Net investment in financing lease at origination	297,824	297,824
Principal repayment and amortization	(18,920)	(14,751)
Net investment in financing lease at period end	278,904	283,073
Less: Current portion	(4,551)	(4,168)
Long term net investment in financing lease	274,353	278,905
Net investment in financing lease consists of:
Financing lease receivable	240,000	247,488
Discounted unguaranteed residual value	38,904	35,585
Net investment in financing lease at period end	$ 278,904	$ 283,073

Discounted unguaranteed residual value.

No definition available.

Name:	hmlp_DirectFinancingLeaseDiscountedUnguaranteedResidualAsset
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Remaining unamortized costs as of the balance sheet date that were essential to acquiring the lease, and that would not otherwise have been incurred without the lease agreement, including evaluating the lessee's credit condition, guarantees, and collateral and costs incurred negotiating, processing, and closing the lease agreement.

+ References

No definition available.

+ Details

Name:	hmlp_DirectFinancingLeaseInitialDirectCosts
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Accumulated repayments and amortization of deferred income and initial direct costs pertaining to direct financing leases.

+ References

No definition available.

+ Details

Name:	hmlp_DirectFinancingLeaseNetInvestmentInLeaseAccumulatedRepaymentsAndAmortization
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of net investment in direct financing lease before repayments and amortization.

+ References

No definition available.

+ Details

Name:	hmlp_DirectFinancingLeaseNetInvestmentInLeaseBeforeRepaymentsAndAmortization
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of net investment in direct financing lease, classified as current.

+ References

No definition available.

+ Details

Name:	hmlp_DirectFinancingLeaseNetInvestmentInLeaseCurrent
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of net investment in direct financing lease, classified as noncurrent.

+ References

No definition available.

+ Details

Name:	hmlp_DirectFinancingLeaseNetInvestmentInLeaseNonCurrent
Namespace Prefix:	hmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The remaining (unamortized) difference between the gross investment in a direct financing lease and the cost or carrying amount, if different, of the leased property as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

+ Details

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

- Definition

Amount of remaining payments as of the balance sheet date that lessees are obligated to make or can be required to make under direct financing leases, including any guarantee of residual value and executory costs. The amount also includes any guaranteed rental payments by an unrelated third-party provided that are financially capable of making such payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

+ Details

Name:	us-gaap_CapitalLeasesNetInvestmentInDirectFinancingLeasesMinimumPaymentsToBeReceived
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The estimate of the lease property's economic value at the end of the direct financing lease term excluding any amounts guaranteed by either the lessee or a third-party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

+ Details

Name:	us-gaap_CapitalLeasesNetInvestmentInDirectFinancingLeasesUnguaranteedResidualValuesOfLeasedProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of net investment in direct financing lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919379-209981

+ Details

Name:	us-gaap_DirectFinancingLeaseNetInvestmentInLease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919391-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919379-209981

+ Details

Name:	us-gaap_SalesTypeAndDirectFinancingLeasesLeaseReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant