Electric utility segment - Regulatory Proceedings (Details) $ in Thousands					1 Months Ended		3 Months Ended		4 Months Ended	9 Months Ended	12 Months Ended
	Jun. 09, 2022 USD ($)	Feb. 16, 2021 agreement	Dec. 23, 2020 USD ($)	Sep. 15, 2020 agreement	Sep. 30, 2023 USD ($) agreement contract project	Jun. 30, 2022 USD ($)	Nov. 30, 2021 agreement	Nov. 30, 2021 entity	Mar. 31, 2023 agreement	Sep. 30, 2023 USD ($) MWh project contract	Dec. 31, 2022 USD ($)	Dec. 31, 2019 USD ($) agreement	Feb. 28, 2023 USD ($)	Jun. 17, 2022 mechanism	Dec. 31, 2021 USD ($)	Jun. 01, 2021 mechanism	Mar. 23, 2021 mechanism	Dec. 31, 2020 entity	Jul. 09, 2020 agreement	Jun. 10, 2019 USD ($)	Oct. 31, 2018 USD ($)
Regulatory Projects and Legal Obligations [Line Items]
PUC proposal period (in days)			45 days
Public utilities, modified pilot process proposal period (in days)										15 days
Propose pilots annual cap										$ 10,000
Potential total annual maximum reward					$ 2,000					$ 2,000
Advanced metering infrastructure term (in years)										3 years
Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
Number of performance incentive mechanisms | mechanism														2		3	2
Multi-year rate period (in years)			5 years
Customer dividend, negative adjustment percentage			0.22%
Savings commitment liability, annual rate			$ 6,600
Recovery of deferral costs	$ 27,800					$ 27,800
Recovery of deferral costs period (in years)	3 years					3 years
Earnings sharing mechanism, actual return on equity, dead band percentage above or below target										3.00%
Approved return on equity, percentage										9.50%
Percentage sharing between customers and utilities										50
Earnings sharing mechanism, actual earning, above or below dead band										1.50%
Percentage sharing for any further difference										90
MPIR and EPRM requested amount										$ 31,100
EPRM approved projects | contract					2					2
EPRM approved projects, capital costs										$ 41,000
Number of projects | project					5					5
Estimated capital costs										$ 488,000
2022 deferred cost recovery approved													$ 400
Decoupling order, service reliability performance, historical measurement period (in years)										10 years
Maximum penalty, percent of ROE										0.20%
Service reliability, pending adjusted maximum penalty amount										$ 6,800
Service reliability, estimated penalties											$ 100
Dead band percentage above or below the target										3.00%
Call center performance, maximum penalty percentage										0.08%
Call center performance, pending adjusted maximum penalty										$ 1,400
Number of power purchase agreements (PPAs) (in agreements) | agreement		1		1	1							7
Incentives accrued					$ 100					$ 100		$ 1,700			$ 100
Number of grid service purchase agreements | agreement																			2
Number of PPAs approved							2	2
Number of GSPAs approved | entity																		2
Number of power purchase agreements terminated | agreement									2
Interpolated RPS rate goal, year one and two (in dollars per MWh) | MWh										20
Interpolated RPS rate goal, year three (in dollars per MWh) | MWh										15
Interpolated RPS rate goal, after year three (in dollars per MWh) | MWh										10
Failure to meet RPS targets, penalty rate (in dollars per MWh) | MWh										20
Potential total annual maximum reward					1,500					$ 1,500
Public utilities, grid services procurement performance incentive mechanism, accrued estimated rewards											40
Potential total annual maximum reward					3,000					3,000
Total annual maximum penalty					900					900
Interconnection approval PIM, accrued estimated rewards											3,000
Performance incentive mechanism, maximum reward					$ 2,000					$ 2,000
Performance incentive mechanism, term (in years)										3 years
Performance incentive mechanism, accrued estimated rewards						$ 500
Target performance historical measurement period (in years)										10 years
Percent of return on equity										0.03%
Pending adjusted amount										$ 1,000
Target performance period (in months)										10 months
Target deadband period (in months)										2 months
Accrued earned rewards, net of penalties											3,400
Hawaiian Electric Company, Inc. and Subsidiaries | COVID-19
Regulatory Projects and Legal Obligations [Line Items]
Public utilities in regulatory assets										$ 8,800
Hawaiian Electric, Parent
Regulatory Projects and Legal Obligations [Line Items]
Public utilities retained percentage										20.00%
Accrued earned rewards, net of penalties											2,500
Hawaii Electric Light Company, Inc
Regulatory Projects and Legal Obligations [Line Items]
Accrued earned rewards, net of penalties											400
Maui Electric
Regulatory Projects and Legal Obligations [Line Items]
Accrued earned rewards, net of penalties											$ 500
Schofield Generation Station | Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
MPIR requested amount										$ 16,500
West Loch PV Project | Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
MPIR requested amount										3,300
Grid Modernization Strategy Phase 1 Project | Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
MPIR requested amount										11,200
Waiawa UFLS Project | Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
EPRM requested amount										$ 100
ERP/EAM Implementation Project | Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory Projects and Legal Obligations [Line Items]
ERP/EAM project service period (in years)										12 years
ERP/EAM project service, savings over 12 years																					$ 246,000
Future O&M expense reductions																				$ 150,000
Future cost avoidance related to capital cost and tax costs																				$ 96,000
Regulatory liability, amortization period (in years)					5 years					5 years
Regulatory liability for O&M expense reductions					$ 11,900					$ 11,900
ERP/EAM Implementation Project | Hawaiian Electric, Parent
Regulatory Projects and Legal Obligations [Line Items]
Regulatory liability for O&M expense reductions					3,000					3,000
ERP/EAM Implementation Project | Hawaii Electric Light Company, Inc
Regulatory Projects and Legal Obligations [Line Items]
Regulatory liability for O&M expense reductions					3,500					3,500
ERP/EAM Implementation Project | Maui Electric
Regulatory Projects and Legal Obligations [Line Items]
Regulatory liability for O&M expense reductions					$ 5,400					$ 5,400