Bank segment (HEI only) - Balance Sheets Data (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 305,551	$ 341,421	$ 196,813
Investment securities
Available-for-sale investment securities	2,574,618	1,970,417
Held-to-maturity investment securities, at amortized cost	522,270	226,947
Held-to-maturity investment securities	510,474
Stock in Federal Home Loan Bank, at cost	10,000	8,680
Loans held for investment			5,120,664
Allowance for credit losses	(71,130)	(101,201)	(53,355)	$ (52,119)
Total loans, net	5,139,984	5,232,642
Loans held for sale, at lower of cost or fair value	10,404	28,275
Other	747,469	629,149
Goodwill	82,190	82,190
Total assets	15,822,637	15,004,007	13,745,251
LIABILITIES AND SHAREHOLDERS’ EQUITY
Other	669,215	618,438
Total liabilities	13,397,460	12,632,212
Commitments and contingencies
Retained earnings	757,921	660,398
Accumulated other comprehensive income (loss), net of taxes
Net unrealized gains (losses) on securities	(32,037)	19,986
Retirement benefit plans	(16,858)	(17,887)
Accumulated other comprehensive income (loss), net of taxes	(52,533)	(1,264)
Total shareholders’ equity	2,390,884	2,337,502	$ 2,280,260	$ 2,162,280
Total capitalization and liabilities	15,822,637	15,004,007
Other assets
Premises and equipment, net	5,392,068	5,265,735
Total other assets	747,469	629,149
Other liabilities
Total other liabilities	669,215	618,438
American Savings Bank (ASB)
Assets
Cash and due from banks	100,051	178,422
Interest-bearing deposits	151,189	114,304
Cash and cash equivalents	251,240	292,726
Investment securities
Available-for-sale investment securities	2,574,618	1,970,417
Held-to-maturity investment securities, at amortized cost	522,270	226,947
Held-to-maturity investment securities	510,474	229,963
Stock in Federal Home Loan Bank, at cost	10,000	8,680
Loans held for investment	5,211,114	5,333,843
Allowance for credit losses	(71,130)	(101,201)
Total loans, net	5,139,984	5,232,642
Loans held for sale, at lower of cost or fair value	10,404	28,275
Other	590,897	554,656
Goodwill	82,190	82,190
Total assets	9,181,603	8,396,533
LIABILITIES AND SHAREHOLDERS’ EQUITY
Deposit liabilities–noninterest-bearing	2,976,632	2,598,500
Deposit liabilities–interest-bearing	5,195,580	4,788,457
Other borrowings	88,305	89,670
Other	193,268	183,731
Total liabilities	8,453,785	7,660,358
Commitments and contingencies
Common stock	1	1
Premium on capital stock	353,895	351,758
Retained earnings	411,704	369,470
Accumulated other comprehensive income (loss), net of taxes
Net unrealized gains (losses) on securities	(32,037)	19,986
Retirement benefit plans	(5,745)	(5,040)
Accumulated other comprehensive income (loss), net of taxes	(37,782)	14,946
Total shareholders’ equity	727,818	736,175
Total capitalization and liabilities	9,181,603	8,396,533
Other assets
Bank-owned life insurance	177,566	163,265
Premises and equipment, net	202,299	206,134
Accrued interest receivable	20,854	24,616
Mortgage servicing rights	9,950	10,020
Low-income housing investments	110,989	83,435
Other	69,239	67,186
Total other assets	590,897	554,656
Other liabilities
Accrued expenses	87,905	62,694
Federal and state income taxes payable	0	6,582
Cashier’s checks	33,675	38,011
Advance payments by borrowers	9,994	10,207
Other	61,694	66,237
Total other liabilities	$ 193,268	$ 183,731