Electric utility segment - Cumulative Preferred Stock (Details)	Dec. 31, 2022 $ / shares
Series C, D, E, H, J and K Preferred Stock \| Hawaiian Electric
Class of Stock [Line Items]
Voluntary liquidation price (in dollars per share)	$ 20
Redemption price (in dollars per share)	21
Series I Preferred Stock \| Hawaiian Electric
Class of Stock [Line Items]
Voluntary liquidation price (in dollars per share)	20
Redemption price (in dollars per share)	20
Series G Preferred Stock \| Hawaii Electric Light Company, Inc. (HELCO)
Class of Stock [Line Items]
Voluntary liquidation price (in dollars per share)	100
Redemption price (in dollars per share)	100
Series H Preferred Stock \| Maui Electric Company, Limited (MECO)
Class of Stock [Line Items]
Voluntary liquidation price (in dollars per share)	100
Redemption price (in dollars per share)	$ 100

The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21488-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21564-112644

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Period Type:	instant