Credit agreements, long-term debt and changes in long-term debt - Schedule of Redemption (Details) - Senior Unsecured Notes - Senior Notes - Hawaiian Electric Company, Inc. and Subsidiaries	Sep. 18, 2025
2028
Debt Instrument, Redemption [Line Items]
Percentage	103.00%
2029
Debt Instrument, Redemption [Line Items]
Percentage	101.50%
2030 and thereafter
Debt Instrument, Redemption [Line Items]
Percentage	100.00%

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration