Environmental Loss Contingency, Statement Of Financial Position, Extensible Enumeration, Not Disclosed Flag

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- Definition

Number Of Kilovolts

+ References

No definition available.

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- Definition

Public Utilities, Renewable Energy Generation Project, Approved Funds

+ References

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- Definition

Public Utilities, Renewable Energy Generation Project, Incurred Cost

+ References

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- Definition

Represents the amount of additional accrued investigation and estimated cleanup costs.

+ References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-10

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (d)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-10

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481899/410-30-55-16

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480102/450-20-S99-1

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-7

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- Definition

Amount, before recovery, of expense for known and estimated future costs arising from requirement to perform environmental remediation.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481899/410-30-55-11

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481960/410-30-45-4

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-12

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- Definition

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.

+ References

No definition available.

+ Details

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Electric utility segment - Utility Projects (Details) $ in Millions		9 Months Ended	12 Months Ended
	Sep. 01, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Nov. 30, 2021 USD ($)	Oct. 31, 2020 transmission_line generationUnit kV
Public Utilities, General Disclosures [Line Items]
Environmental loss contingency, statement of financial position, not disclosed		reserve account balance
Maui Electric
Public Utilities, General Disclosures [Line Items]
Additional accrued investigation and estimated cleanup costs		$ 2.6
Hawaiian Electric, Parent \| PCB Contamination
Public Utilities, General Disclosures [Line Items]
Valuation allowances and reserves		9.7
Hawaiian Electric, Parent \| Kapolei Petroleum Contamination \| James Campbell Company
Public Utilities, General Disclosures [Line Items]
Environmental remediation expense	$ 1.2		$ 0.8
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		$ 24.7