Bank segment (HEI only) - Allowance For Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for credit losses:
Beginning balance	$ 72,216	$ 71,130	$ 101,201
Charge-offs	(13,319)	(6,830)	(9,700)
Recoveries	5,818	5,379	6,054
Net (charge-offs) recoveries	(7,501)	(1,451)	(3,646)
Provision for credit losses	9,657	2,537	(26,425)
Ending balance	74,372	72,216	71,130
Average loans outstanding	$ 6,113,467	$ 5,456,952	$ 5,220,491
Net charge-offs (recoveries) to average loans	0.12%	0.03%	0.07%
Real estate | Residential 1-4 family
Allowance for credit losses:
Beginning balance	$ 6,270	$ 6,545	$ 4,600
Charge-offs	(994)	(13)	(67)
Recoveries	89	79	92
Net (charge-offs) recoveries	(905)	66	25
Provision for credit losses	2,070	(341)	1,920
Ending balance	7,435	6,270	6,545
Average loans outstanding	$ 2,523,767	$ 2,331,473	$ 2,155,322
Net charge-offs (recoveries) to average loans	0.04%	0.00%	0.00%
Real estate | Commercial real estate
Allowance for credit losses:
Beginning balance	$ 21,898	$ 24,696	$ 35,607
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Provision for credit losses	287	(2,798)	(10,911)
Ending balance	22,185	21,898	24,696
Average loans outstanding	$ 1,380,924	$ 1,204,756	$ 1,046,276
Net charge-offs (recoveries) to average loans	0.00%	0.00%	0.00%
Real estate | Home equity line of credit
Allowance for credit losses:
Beginning balance	$ 6,125	$ 5,657	$ 6,813
Charge-offs	(375)	0	(45)
Recoveries	176	71	113
Net (charge-offs) recoveries	(199)	71	68
Provision for credit losses	1,852	397	(1,224)
Ending balance	7,778	6,125	5,657
Average loans outstanding	$ 1,030,983	$ 918,563	$ 885,759
Net charge-offs (recoveries) to average loans	0.02%	(0.01%)	(0.01%)
Real estate | Residential land
Allowance for credit losses:
Beginning balance	$ 717	$ 646	$ 609
Charge-offs	0	0	0
Recoveries	4	104	61
Net (charge-offs) recoveries	4	104	61
Provision for credit losses	(100)	(33)	(24)
Ending balance	621	717	646
Average loans outstanding	$ 20,077	$ 21,442	$ 18,227
Net charge-offs (recoveries) to average loans	(0.02%)	(0.49%)	(0.33%)
Real estate | Commercial construction
Allowance for credit losses:
Beginning balance	$ 1,195	$ 2,186	$ 4,149
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Provision for credit losses	2,408	(991)	(1,963)
Ending balance	3,603	1,195	2,186
Average loans outstanding	$ 127,332	$ 90,021	$ 111,711
Net charge-offs (recoveries) to average loans	0.00%	0.00%	0.00%
Real estate | Residential construction
Allowance for credit losses:
Beginning balance	$ 46	$ 18	$ 11
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Provision for credit losses	(3)	28	7
Ending balance	43	46	18
Average loans outstanding	$ 17,634	$ 18,317	$ 11,361
Net charge-offs (recoveries) to average loans	0.00%	0.00%	0.00%
Commercial
Allowance for credit losses:
Beginning balance	$ 12,426	$ 15,798	$ 25,462
Charge-offs	(723)	(563)	(1,561)
Recoveries	1,983	1,288	1,468
Net (charge-offs) recoveries	1,260	725	(93)
Provision for credit losses	(4,564)	(4,097)	(9,571)
Ending balance	9,122	12,426	15,798
Average loans outstanding	$ 754,601	$ 710,658	$ 856,226
Net charge-offs (recoveries) to average loans	(0.17%)	(0.10%)	0.01%
Consumer
Allowance for credit losses:
Beginning balance	$ 23,539	$ 15,584	$ 23,950
Charge-offs	(11,227)	(6,254)	(8,027)
Recoveries	3,566	3,837	4,320
Net (charge-offs) recoveries	(7,661)	(2,417)	(3,707)
Provision for credit losses	7,707	10,372	(4,659)
Ending balance	23,585	23,539	15,584
Average loans outstanding	$ 258,149	$ 161,722	$ 135,609
Net charge-offs (recoveries) to average loans	2.97%	1.49%	2.73%