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

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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

Percentage of public utility's approved equity to capital, including debt and equity.

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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		6 Months Ended
	Jan. 31, 2024 USD ($)	Jul. 31, 2025	Sep. 30, 2020 MW	Jun. 30, 2025 USD ($)	Aug. 07, 2024 USD ($)	Dec. 31, 2023 USD ($)
Hawaiian Electric Company, Inc. and Subsidiaries
Public Utilities, General Disclosures [Line Items]
Public utilities, project cost recovery cap					$ 95.0
Project costs incurred				$ 27.0
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				$ 9.7
Waena Battery Energy Storage System Project \| Hawaiian Electric Company, Inc. and Subsidiaries \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Public utilities, approved estimated capital costs (as percent)		20.00%
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 (in years)	5 years