Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
General payment period	30 days
Revenues from contracts with customers	$ 3,465,215	$ 2,521,425
Revenues from other sources	276,770	328,954
Total revenues	3,741,985	2,850,379	$ 2,579,775
Services/goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48,883	46,658
Services/goods transferred over time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,416,332	2,474,767
Electric energy sales - residential
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,078,372	830,653
Electric energy sales - commercial
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,087,485	791,424
Electric energy sales - large light and power
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,221,608	837,834
Electric energy sales - other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17,063	10,770
Bank fees
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48,883	46,658
Other sales
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,804	4,086
Regulatory revenue
Disaggregation of Revenue [Line Items]
Revenues from other sources	(29,124)	40,069
Bank interest and dividend income
Disaggregation of Revenue [Line Items]
Revenues from other sources	265,874	242,266
Other bank noninterest income
Disaggregation of Revenue [Line Items]
Revenues from other sources	6,311	17,474
Other
Disaggregation of Revenue [Line Items]
Revenues from other sources	33,709	29,145
Hawaiian Electric Company, Inc. and Subsidiaries
Disaggregation of Revenue [Line Items]
Revenue taxes, other than income tax expense	303,000	226,000	202,000
Revenue taxes accrued	188,000	128,000
Electric utility
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,404,528	2,470,681
Revenues from other sources	4,059	68,955
Total revenues	3,408,587	2,539,636	2,265,320
Electric utility | Services/goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Electric utility | Services/goods transferred over time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,404,528	2,470,681
Electric utility | Electric energy sales - residential
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,078,372	830,653
Electric utility | Electric energy sales - commercial
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,087,485	791,424
Electric utility | Electric energy sales - large light and power
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,221,608	837,834
Electric utility | Electric energy sales - other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17,063	10,770
Electric utility | Bank fees
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Electric utility | Other sales
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Electric utility | Regulatory revenue
Disaggregation of Revenue [Line Items]
Revenues from other sources	(29,124)	40,069
Electric utility | Bank interest and dividend income
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Electric utility | Other bank noninterest income
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Electric utility | Other
Disaggregation of Revenue [Line Items]
Revenues from other sources	33,183	28,886
Bank
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48,883	46,658
Revenues from other sources	272,185	259,740
Total revenues	321,068	306,398	313,511
Bank | Services/goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48,883	46,658
Bank | Services/goods transferred over time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Electric energy sales - residential
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Electric energy sales - commercial
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Electric energy sales - large light and power
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Electric energy sales - other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Bank fees
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48,883	46,658
Bank | Other sales
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Bank | Regulatory revenue
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Bank | Bank interest and dividend income
Disaggregation of Revenue [Line Items]
Revenues from other sources	265,874	242,266
Bank | Other bank noninterest income
Disaggregation of Revenue [Line Items]
Revenues from other sources	6,311	17,474
Bank | Other
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,804	4,086
Revenues from other sources	526	259
Total revenues	12,330	4,345	$ 944
Other | Services/goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Services/goods transferred over time
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,804	4,086
Other | Electric energy sales - residential
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Electric energy sales - commercial
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Electric energy sales - large light and power
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Electric energy sales - other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Bank fees
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Other | Other sales
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,804	4,086
Other | Regulatory revenue
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Other | Bank interest and dividend income
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Other | Other bank noninterest income
Disaggregation of Revenue [Line Items]
Revenues from other sources	0	0
Other | Other
Disaggregation of Revenue [Line Items]
Revenues from other sources	$ 526	$ 259