Bank segment (HEI only) - Statements of Income Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Interest expense
Interest on deposit liabilities	$ 7,327	$ 4,981	$ 10,654
Total interest expense	116,703	99,403	99,808
Noninterest income
Noninterest income	3,465,215	2,521,425
Noninterest expense
Income before income taxes	304,195	310,863	240,624
Income taxes	61,167	62,807	40,910
Net income	243,028	248,056	199,714
Current period other comprehensive income (loss) and reclassifications, net of taxes	(283,495)	(51,269)	18,775
Comprehensive income attributable to Hawaiian Electric Industries, Inc.	(42,357)	194,897	216,599
COVID-19 related costs			5,100
Incremental compensation expense			2,500
Enhanced cleaning and sanitation costs			2,000
American Savings Bank (ASB)
Interest and dividend income
Interest and fees on loans	207,830	198,802	214,134
Interest and dividends on investment securities	58,044	43,464	30,529
Total interest and dividend income	265,874	242,266	244,663
Interest expense
Interest on deposit liabilities	7,327	4,981	10,654
Interest on other borrowings	5,974	59	460
Total interest expense	13,301	5,040	11,114
Net interest income	252,573	237,226	233,549
Provision for credit losses	2,037	(25,825)	50,811
Net interest income after provision for credit losses	250,536	263,051	182,738
Noninterest income
Gain on sale of real estate	1,778	0	0
Gain on sale of investment securities, net	0	528	9,275
Total noninterest income	56,972	64,660	78,123
Noninterest expense
Compensation and employee benefits	113,839	113,970	104,443
Occupancy	24,026	20,584	21,573
Data processing	17,681	17,634	14,769
Services	10,679	10,327	11,121
Equipment	10,100	9,510	9,001
Office supplies, printing and postage	4,398	4,239	4,623
Marketing	3,968	3,870	3,435
FDIC insurance	3,591	3,235	2,342
Other expense	16,985	13,783	20,283
Total noninterest expense	205,267	197,152	191,590
Income before income taxes	102,241	130,559	69,271
Income taxes	22,252	29,325	11,688
Net income	79,989	101,234	57,583
Current period other comprehensive income (loss) and reclassifications, net of taxes	(298,833)	(52,728)	23,608
Comprehensive income attributable to Hawaiian Electric Industries, Inc.	(218,844)	48,506	81,191
American Savings Bank (ASB) | Fees from other financial services
Noninterest income
Noninterest income	19,830	21,225	16,447
American Savings Bank (ASB) | Fee income on deposit liabilities
Noninterest income
Noninterest income	18,762	16,663	16,059
American Savings Bank (ASB) | Fee income on other financial products
Noninterest income
Noninterest income	10,291	8,770	6,381
American Savings Bank (ASB) | Bank-owned life insurance
Noninterest income
Noninterest income	2,533	7,318	6,483
American Savings Bank (ASB) | Mortgage banking income
Noninterest income
Noninterest income	1,692	9,305	23,734
American Savings Bank (ASB) | Other income, net
Noninterest income
Noninterest income	$ 2,086	$ 851	$ (256)