Bank segment - Income statement data (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Noninterest income
Noninterest income	$ 822,384	$ 700,831
Noninterest expense
Income before income taxes	70,304	87,480
Income taxes	15,110	17,840
Net income attributable to Hawaiian Electric	55,194	69,640
Other comprehensive (loss) income, net of tax benefits	20,488	(117,159)
Comprehensive income (loss) attributable to Hawaiian Electric Industries, Inc.	75,209	(47,992)
American Savings Bank (ASB)
Interest and dividend income
Interest and fees on loans	64,842	46,005
Interest and dividends on investment securities	14,637	13,984
Total interest and dividend income	79,479	59,989
Interest expense
Interest on deposit liabilities	6,837	947
Interest on other borrowings	7,721	5
Total interest expense	14,558	952
Net interest income	64,921	59,037
Provision for credit losses	1,175	(3,263)
Net interest income after provision for credit losses	63,746	62,300
Noninterest income
Gain on sale of real estate	0	1,002
Total noninterest income	14,378	16,128
Noninterest expense
Compensation and employee benefits	30,204	27,215
Occupancy	5,588	5,952
Data processing	5,012	4,151
Services	2,595	2,439
Equipment	2,646	2,329
Office supplies, printing and postage	1,165	1,060
Marketing	1,016	1,018
Other expense	6,191	4,049
Total noninterest expense	54,417	48,213
Income before income taxes	23,707	30,215
Income taxes	5,145	6,345
Net income attributable to Hawaiian Electric	18,562	23,870
Other comprehensive (loss) income, net of tax benefits	18,430	(122,441)
Comprehensive income (loss) attributable to Hawaiian Electric Industries, Inc.	36,992	(98,571)
American Savings Bank (ASB) | Fees from other financial services
Noninterest income
Noninterest income	4,679	5,587
American Savings Bank (ASB) | Fee income on deposit liabilities
Noninterest income
Noninterest income	4,599	4,691
American Savings Bank (ASB) | Fee income on other financial products
Noninterest income
Noninterest income	2,744	2,718
American Savings Bank (ASB) | Bank-owned life insurance
Noninterest income
Noninterest income	1,425	681
American Savings Bank (ASB) | Mortgage banking income
Noninterest income
Noninterest income	130	1,077
American Savings Bank (ASB) | Other income, net
Noninterest income
Noninterest income	$ 801	$ 372