Bank segment (HEI only) - Available For Sale Investment Securities (Details) $ in Thousands	Dec. 31, 2022 USD ($) issue	Dec. 31, 2021 USD ($) issue
Available-for-sale
Amortized cost	$ 1,678,205
Available-for-sale investment securities	1,429,667	$ 2,574,618
Held-to-maturity
Amortized cost	1,251,747	522,270
Held-to-maturity investment securities	1,150,971
American Savings Bank (ASB)
Available-for-sale
Amortized cost	1,678,205	2,618,384
Gross unrealized gains	0	7,969
Gross unrealized losses	(248,538)	(51,735)
Available-for-sale investment securities	$ 1,429,667	$ 2,574,618
Number of issues, less than 12 months \| issue	129	125
Fair value, less than 12 months	$ 526,681	$ 1,902,850
Gross unrealized losses, less than 12 months	$ (61,147)	$ (38,850)
Number of issues, more than 12 months \| issue	75	18
Fair value, 12 months or longer	$ 888,084	$ 271,012
Gross unrealized losses, 12 months or longer	(187,391)	(12,885)
Held-to-maturity
Amortized cost	1,251,747	522,270
Gross unrealized gains	2,670	1,648
Gross unrealized losses	(103,446)	(13,444)
Held-to-maturity investment securities	$ 1,150,971	$ 510,474
Number of issues, less than 12 months \| issue	23	24
Fair value, less than 12 months	$ 200,503	$ 330,477
Gross unrealized losses, less than 12 months	$ (13,815)	$ (7,835)
Number of issues, more than 12 months \| issue	53	7
Fair value, 12 months or longer	$ 601,792	$ 106,483
Gross unrealized losses, 12 months or longer	(89,631)	(5,609)
American Savings Bank (ASB) \| U.S. Treasury and federal agency obligations
Available-for-sale
Amortized cost	88,344	89,714
Gross unrealized gains	0	803
Gross unrealized losses	(7,281)	(427)
Available-for-sale investment securities	$ 81,063	$ 90,090
Number of issues, less than 12 months \| issue	12	4
Fair value, less than 12 months	$ 41,201	$ 44,827
Gross unrealized losses, less than 12 months	$ (2,120)	$ (427)
Number of issues, more than 12 months \| issue	4	0
Fair value, 12 months or longer	$ 39,862	$ 0
Gross unrealized losses, 12 months or longer	(5,161)	0
Held-to-maturity
Amortized cost	59,894	59,871
Gross unrealized gains	0	168
Gross unrealized losses	(8,478)	(170)
Held-to-maturity investment securities	$ 51,416	$ 59,869
Number of issues, less than 12 months \| issue	1	2
Fair value, less than 12 months	$ 16,874	$ 39,594
Gross unrealized losses, less than 12 months	$ (3,222)	$ (170)
Number of issues, more than 12 months \| issue	2	0
Fair value, 12 months or longer	$ 34,542	$ 0
Gross unrealized losses, 12 months or longer	(5,256)	0
American Savings Bank (ASB) \| Mortgage-backed securities — issued or guaranteed by U.S. Government agencies or sponsored agencies
Available-for-sale
Amortized cost	1,530,582	2,482,618
Gross unrealized gains	0	6,511
Gross unrealized losses	(237,614)	(51,206)
Available-for-sale investment securities	$ 1,292,968	$ 2,437,923
Number of issues, less than 12 months \| issue	113	120
Fair value, less than 12 months	$ 455,836	$ 1,845,243
Gross unrealized losses, less than 12 months	$ (56,999)	$ (38,321)
Number of issues, more than 12 months \| issue	70	18
Fair value, 12 months or longer	$ 837,132	$ 271,012
Gross unrealized losses, 12 months or longer	(180,615)	(12,885)
Held-to-maturity
Amortized cost	1,191,853	462,399
Gross unrealized gains	2,670	1,480
Gross unrealized losses	(94,968)	(13,274)
Held-to-maturity investment securities	$ 1,099,555	$ 450,605
Number of issues, less than 12 months \| issue	22	22
Fair value, less than 12 months	$ 183,629	$ 290,883
Gross unrealized losses, less than 12 months	$ (10,593)	$ (7,665)
Number of issues, more than 12 months \| issue	51	7
Fair value, 12 months or longer	$ 567,250	$ 106,483
Gross unrealized losses, 12 months or longer	(84,375)	(5,609)
American Savings Bank (ASB) \| Corporate bonds
Available-for-sale
Amortized cost	44,377	30,625
Gross unrealized gains	0	655
Gross unrealized losses	(3,643)	(102)
Available-for-sale investment securities	$ 40,734	$ 31,178
Number of issues, less than 12 months \| issue	4	1
Fair value, less than 12 months	$ 29,644	$ 12,780
Gross unrealized losses, less than 12 months	$ (2,028)	$ (102)
Number of issues, more than 12 months \| issue	1	0
Fair value, 12 months or longer	$ 11,090	$ 0
Gross unrealized losses, 12 months or longer	(1,615)	0
American Savings Bank (ASB) \| Mortgage revenue bonds
Available-for-sale
Amortized cost	14,902	15,427
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Available-for-sale investment securities	$ 14,902	$ 15,427
Number of issues, less than 12 months \| issue	0	0
Fair value, less than 12 months	$ 0	$ 0
Gross unrealized losses, less than 12 months	$ 0	$ 0
Number of issues, more than 12 months \| issue	0	0
Fair value, 12 months or longer	$ 0	$ 0
Gross unrealized losses, 12 months or longer	$ 0	$ 0

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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