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Represents the consolidated subsidiary debt to total consolidated capitalization ratio which the entity is required to maintain pursuant to a debt covenant.

No definition available.

Name:	he_DebtInstrumentCovenantConsolidatedSubsidiaryDebtToTotalConsolidatedCapitalizationRatio
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Data Type:	num:percentItemType
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Period Type:	instant

Represents the nonconsolidated capitalization ratio, which the entity is required to maintain pursuant to a debt covenant.

No definition available.

Name:	he_DebtInstrumentCovenantNonconsolidatedCapitalizationRatio
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Data Type:	num:percentItemType
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Debt Instrument, Number Of Instruments Entered Into During Period

No definition available.

Name:	he_DebtInstrumentNumberOfInstrumentsEnteredIntoDuringPeriod
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Data Type:	xbrli:integerItemType
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Represents the number of financial institutions with which the entity entered into a revolving Non Collateralized credit agreement with a letter of credit sub-facility.

No definition available.

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

No definition available.

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Data Type:	num:percentItemType
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Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Data Type:	xbrli:durationItemType
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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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

Name:	us-gaap_LineOfCreditFacilityAbstract
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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.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Balance Type:	debit
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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.

No definition available.

Name:	us-gaap_ShortTermDebtLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Weighted average interest rate of short-term debt outstanding calculated at point in time.

Name:	us-gaap_ShortTermDebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Name:	srt_RangeAxis=srt_MaximumMember
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
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Data Type:	na
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Name:	srt_CounterpartyNameAxis=he_HamakuaEnergyPartnersLPMember
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Data Type:	na
Balance Type:
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
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Data Type:	na
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Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
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Data Type:	na
Balance Type:
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Name:	dei_LegalEntityAxis=he_HawaiianElectricCompanyAndSubsidiariesMember
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Data Type:	na
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Name:	dei_LegalEntityAxis=he_HawaiianElectricParentMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=he_TermLoanCreditAgreementMaturingNovember2019Member
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