Long-term Contract For Purchase Of Electric Power, Total Contracted Battery Energy Storage System Capacity

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Number Of Kilovolts

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- Definition

Public Utilities, Electric Grid Project, Approved Funds

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- Definition

Public Utilities, Electric Grid Project, Period

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- Definition

Public Utilities, Project Cost Recovery Cap

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- Definition

Public Utilities, Project Costs Incurred

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- Definition

Public Utilities, Renewable Energy Generation Project, Approved Funds

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- Definition

Public Utilities, Renewable Energy Generation Project, Incurred Cost

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- Definition

Public Utilities, Renewable Energy Generation Project, Number Of Extended Transmission Lines

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- Definition

Public Utilities, Renewable Energy Generation Project, Number Of Generating Units Converting To Synchronous Condensers

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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.

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Electric utility segment - Utility Projects (Details) $ in Millions		1 Months Ended	3 Months Ended
	Jan. 31, 2024 USD ($)	Sep. 30, 2020 MW	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Aug. 29, 2023 USD ($)	Nov. 30, 2021 USD ($)	Oct. 31, 2020 transmission_line generationUnit kV
Hawaiian Electric Company, Inc. and Subsidiaries
Public Utilities, General Disclosures [Line Items]
Public utilities, project cost recovery cap					$ 95.0
Project costs incurred			$ 1.5
Waena Switchyard/Synchronous Condenser Project \| Hawaiian Electric Company, Inc. and Subsidiaries
Public Utilities, General Disclosures [Line Items]
Number of extended transmission lines \| transmission_line							2
Number of kilovolts \| kV							69
Number of generating units converting to synchronous condensers \| generationUnit							2
Renewable energy generation project, approved funds						$ 38.8
Renewable energy generation project, incurred cost			25.3
Waena Battery Energy Storage System Project
Public Utilities, General Disclosures [Line Items]
Total contracted battery energy storage system capacity \| MW		40
Waena Battery Energy Storage System Project \| Hawaiian Electric Company, Inc. and Subsidiaries
Public Utilities, General Disclosures [Line Items]
Renewable energy generation project, approved funds				$ 82.1
Renewable energy generation project, incurred cost			$ 0.6
Climate Adaptation Transmission And Distribution Resilience Program \| Hawaiian Electric Company, Inc. and Subsidiaries
Public Utilities, General Disclosures [Line Items]
Public utilities, electric grid project, approved funds	$ 189.7
Project period	5 years