Bank segment (HEI only) - Deposit Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Weighted-average stated rate
Savings	0.03%	0.03%
Checking, interest-bearing	0.17%	0.02%
Checking, noninterest-bearing	0.00%	0.00%
Commercial checking	0.00%	0.00%
Money market	0.82%	0.06%
Time certificates	2.39%	0.67%
Weighted-average stated rate	0.24%	0.05%
Deposit liabilities
Savings	$ 3,198,329	$ 3,234,646
Checking
Interest-bearing	1,359,519	1,344,049
Noninterest-bearing	1,453,937	1,472,727
Commercial checking	1,357,140	1,503,905
Money market	189,053	192,909
Time certificates	611,718	423,976
Amount	8,169,696	8,172,212
Certificate accounts of $250,000 or more	346,900	87,600
Term certificates outstanding, scheduled maturities
2023	495,577
2024	59,493
2025	34,360
2026	11,224
2027	8,327
Thereafter	2,737
Total	611,718
Overdrawn deposit accounts classified as loans	1,500	1,300
Interest expense on deposit liabilities by type of deposit
Time certificates	5,372	3,805	$ 7,944
Savings	860	802	1,774
Money market	330	132	465
Interest-bearing checking	765	242	471
Interest expense on deposit liabilities	$ 7,327	$ 4,981	$ 10,654

Interest expense incurred on all interest-bearing checking.

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Amount of noninterest-bearing domestic commercial checking deposit liabilities.

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Overdrawn Deposit Accounts

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Weighted Average Rate Domestic Deposit, Checking, Noninterest-Bearing

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Weighted Average Rate Domestic Deposit, Commercial Checking

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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Amount of interest-bearing domestic certificate of deposit liabilities.

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Amount of interest-bearing domestic checking deposit liabilities.

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Amount of interest-bearing domestic money market demand account deposit liabilities.

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Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

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Aggregate amount of interest expense on all deposits.

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Interest expense incurred on all money market deposits.

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Interest expense incurred on all savings account deposits.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)

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The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

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Amount of noninterest-bearing domestic checking deposit liabilities.

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Amount of time deposit maturing after fifth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 470
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Amount of time deposit maturing in fifth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in fourth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in next fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in third fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in second fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit liabilities, including certificates of deposit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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Weighted average interest rate calculated at point in time for domestic deposit liability.

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The weighted average interest rate for domestic certificates of deposit liabilities.

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The weighted average interest rate for domestic checking deposit liabilities.

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The weighted average interest rate for domestic money market demand account deposit liabilities.

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The weighted average interest rate for domestic savings deposit liabilities.

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