Maui windstorm and wildfires - Utilities Charged (Details) - Natural Disasters and Other Casualty Events - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Maui Windstorm and Wildfires
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	$ 59,834	$ 235,504	$ 89,395	$ 2,013,574
Insurance recoveries	(49,070)	(52,158)	(53,374)	(83,610)
Deferral treatment approved by the PUC	(6,237)	(8,589)	(21,809)	(24,143)
Total Maui windstorm and wildfires related expenses, net of insurance recoveries and approved deferral treatment	4,527	174,757	14,212	1,905,821
Proposed settlement of securities	47,800		47,800
Legal expenses
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	5,794	17,205	20,532	56,330
Wildfire securities-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	47,750		47,750
Wildfire tort-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses		203,000		1,915,000
Other expense
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	6,290	15,299	21,113	42,244
Hawaiian Electric Company, Inc. and Subsidiaries | Maui Windstorm and Wildfires
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	10,238	228,250	32,290	1,991,692
Insurance recoveries	(430)	(49,625)	126	(75,973)
Deferral treatment approved by the PUC	(6,237)	(8,589)	(21,809)	(24,143)
Total Maui windstorm and wildfires related expenses, net of insurance recoveries and approved deferral treatment	3,571	170,036	10,607	1,891,576
Adjustments amount	1,000		7,600
Deferred to a regulatory asset	500		4,500
Income related to discontinued operations		900		1,200
Hawaiian Electric Company, Inc. and Subsidiaries | Legal expenses
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	4,316	11,821	12,469	40,169
Hawaiian Electric Company, Inc. and Subsidiaries | Wildfire securities-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	0		0
Hawaiian Electric Company, Inc. and Subsidiaries | Wildfire tort-related claims
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses		203,000		1,915,000
Hawaiian Electric Company, Inc. and Subsidiaries | Other expense
Public Utilities, General Disclosures [Line Items]
Total Maui windstorm and wildfires related expenses	$ 5,922	$ 13,429	$ 19,821	$ 36,523