v3.26.1
Electric utility segment - Regulatory Assets and Liability (Details) - Hawaiian Electric Company, Inc. and Subsidiaries - USD ($)
$ in Millions
Dec. 31, 2025
Jun. 30, 2026
Wildfire Mitigation Plan (WMP) (to be determined by the PUC)    
Regulatory Projects and Legal Obligations [Line Items]    
Regulatory assets   $ 21.4
Target reduction risk, period 3 years  
Suspension of Disconnections    
Regulatory Projects and Legal Obligations [Line Items]    
Regulatory assets   7.1
Natural Disasters and Other Casualty Events    
Regulatory Projects and Legal Obligations [Line Items]    
Regulatory assets   $ 80.5