XML 59 R46.htm IDEA: XBRL DOCUMENT
v3.23.1

Electric utility segment - Regulatory assets for COVID-19 related costs (Details) - Hawaiian Electric Company, Inc. and Subsidiaries - USD ($) $ in Millions |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | ---
Jun. 09, 2022 | Dec. 31, 2021 | Mar. 31, 2023
Regulatory Projects and Legal Obligations [Line Items] |  |  |
Recovery of deferral costs | $ 27.8 |  |
Recovery of deferral costs period | 3 years |  |
COVID-19 |  |  |
Regulatory Projects and Legal Obligations [Line Items] |  |  |
Customer bill forgiveness |  | $ 2.0 |
Public utilities in regulatory assets |  |  | $ 9.6

X
- Definition Customer Bill Forgiveness + References No definition available. + Details
Name: | he_CustomerBillForgiveness
Namespace Prefix: | he_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Public Utilities In Regulatory Assets + References No definition available. + Details
Name: | he_PublicUtilitiesInRegulatoryAssets
Namespace Prefix: | he_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Recovery Of Deferral Costs, CARES Act + References No definition available. + Details
Name: | he_RecoveryOfDeferralCostsCARESAct
Namespace Prefix: | he_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Recovery Of Deferral Costs, CARES Act, Period + References No definition available. + Details
Name: | he_RecoveryOfDeferralCostsCARESActPeriod
Namespace Prefix: | he_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | he_RegulatoryProjectsAndLegalObligationsLineItems
Namespace Prefix: | he_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=he_HawaiianElectricCompanyAndSubsidiariesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=he_COVID19Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |