Share-based compensation - Schedule of Share-Based Compensation Expense and Related Income Tax Benefit (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-based compensation
Share-based compensation expense	$ 1.2	$ 0.8
Income tax benefit	0.1	0.1
Hawaiian Electric Company, Inc. and Subsidiaries
Share-based compensation
Share-based compensation expense	0.8	0.5
Income tax benefit	$ 0.1	$ 0.1

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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+ Details

HAWAIIAN ELECTRIC INDUSTRIES INC 10-Q