Bank segment (HEI only) - Statements of Income Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest expense
Interest on deposit liabilities	$ 4,981	$ 10,654	$ 16,830
Total interest expense	99,403	99,808	109,339
Provision for credit losses	(26,425)	49,811	23,480
Noninterest income
Noninterest income	2,521,425	2,269,451
Noninterest expense
Income before income taxes	310,863	240,624	271,409
Income taxes	62,807	40,910	51,637
Net income (loss)	248,056	199,714	219,772
Current period other comprehensive income (loss) and reclassifications, net of taxes	(51,269)	18,775	30,571
Comprehensive income	194,897	216,599	248,453
COVID-19 related costs	600	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	198,802	214,134	233,632
Interest and dividends on investment securities	43,464	30,529	32,922
Total interest and dividend income	242,266	244,663	266,554
Interest expense
Interest on deposit liabilities	4,981	10,654	16,830
Interest on other borrowings	59	460	1,610
Total interest expense	5,040	11,114	18,440
Net interest income	237,226	233,549	248,114
Provision for credit losses	(25,825)	50,811	23,480
Net interest income after provision for credit losses	263,051	182,738	224,634
Noninterest income
Gain on sale of real estate	0	0	10,762
Gain on sale of investment securities, net	528	9,275	653
Total noninterest income	64,660	78,123	72,778
Noninterest expense
Compensation and employee benefits	113,970	104,443	103,009
Occupancy	20,584	21,573	21,272
Data processing	17,634	14,769	15,306
Services	10,327	11,121	10,239
Equipment	9,510	9,001	8,760
Office supplies, printing and postage	4,239	4,623	5,512
Marketing	3,870	3,435	4,490
FDIC insurance	3,235	2,342	1,204
Other expense	13,783	20,283	15,586
Total noninterest expense	197,152	191,590	185,378
Income before income taxes	130,559	69,271	112,034
Income taxes	29,325	11,688	23,061
Net income (loss)	101,234	57,583	88,973
Current period other comprehensive income (loss) and reclassifications, net of taxes	(52,728)	23,608	29,406
Comprehensive income	48,506	81,191	118,379
American Savings Bank (ASB) | Fees from other financial services
Noninterest income
Noninterest income	21,225	16,447	19,275
American Savings Bank (ASB) | Fee income on deposit liabilities
Noninterest income
Noninterest income	16,663	16,059	20,877
American Savings Bank (ASB) | Fee income on other financial products
Noninterest income
Noninterest income	8,770	6,381	6,507
American Savings Bank (ASB) | Bank-owned life insurance
Noninterest income
Noninterest income	7,318	6,483	7,687
American Savings Bank (ASB) | Mortgage banking income
Noninterest income
Noninterest income	9,305	23,734	4,943
American Savings Bank (ASB) | Other income, net
Noninterest income
Noninterest income	$ 851	$ (256)	$ 2,074