Maui windstorm and wildfires - Utilities Charged (Details) - Natural Disasters and Other Casualty Events - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Maui Windstorm and Wildfires
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	$ 1,748,295	$ 1,778,413	$ 138,383
Insurance recovery	(18,875)	(31,452)	(104,580)
Deferral treatment approved by the PUC	(7,656)	(15,554)	(14,692)
Total Maui windstorm and wildfires related expenses, net of insurance recoveries and approved deferral treatment	1,721,764	1,731,407	19,111
Legal expenses
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	25,000	40,027	34,876
Wildfire tort-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	1,712,000	1,712,000	75,000
Other expense
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	11,295	26,386	28,507
Hawaiian Electric Company, Inc. and Subsidiaries \| Maui Windstorm and Wildfires
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	1,738,875	1,763,442	114,808
Insurance recovery	(16,379)	(26,348)	(98,613)
Deferral treatment approved by the PUC	(7,656)	(15,554)	(14,692)
Total Maui windstorm and wildfires related expenses, net of insurance recoveries and approved deferral treatment	1,714,840	1,721,540	1,503
Hawaiian Electric Company, Inc. and Subsidiaries \| Legal expenses
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	17,613	28,348	24,737
Hawaiian Electric Company, Inc. and Subsidiaries \| Wildfire tort-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	1,712,000	1,712,000	75,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Other expense
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	$ 9,262	$ 23,094	$ 15,071

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Loss Contingencies, Net Of Recoveries And Reclassifications Of Payments

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The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(3))
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The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake).

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-Topic 220
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