XML 49 R33.htm IDEA: XBRL DOCUMENT
v3.21.2

Electric utility segment - Unconsolidated variable interest entities (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 entity MW | Mar. 31, 2021 MW | Jun. 30, 2021 agreement entity
Power purchase agreement |  |  |
Number of IPPs (in entities) | entity | 3 |  | 3
Puna Geothermal Venture Power Purchase Agreement |  |  |
Power purchase agreement |  |  |
Firm capacity volume (in megawatts) | MW | 23.9 | 13 |
Hawaiian Electric Company |  |  |
Power purchase agreement |  |  |
Number of power purchase agreements (PPAs) (in agreements) | agreement |  |  | 5

X
- Definition Represents the number of firm power purchase agreements entered into, by the company. + References No definition available. + Details
Name: | he_NumberOfPowerPurchaseAgreements
Namespace Prefix: | he_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Power Purchase Agreement, Firm Capacity Volume + References No definition available. + Details
Name: | he_PowerPurchaseAgreementFirmCapacityVolume
Namespace Prefix: | he_
Data Type: | dtr-types:powerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Variable Interest Entity Number Of Consolidated VIEs + References No definition available. + Details
Name: | he_VariableInterestEntityNumberOfConsolidatedVIEs
Namespace Prefix: | he_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_LongTermContractForPurchaseOfElectricPowerAxis=he_PunaGeothermalVenturePowerPurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=srt_SubsidiariesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |