Bank segment (HEI only) - Deposit Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Weighted-average stated rate
Savings	0.15%	0.03%
Checking, interest-bearing	0.85%	0.17%
Checking, noninterest-bearing	0.00%	0.00%
Commercial checking	0.00%	0.00%
Money market	3.52%	0.82%
Time certificates	3.99%	2.39%
Weighted-average stated rate	0.85%	0.24%
Deposit liabilities
Savings	$ 2,765,175	$ 3,198,329
Checking
Interest-bearing	1,427,225	1,359,519
Noninterest-bearing	1,383,197	1,453,937
Commercial checking	1,216,565	1,357,140
Money market	289,709	189,053
Time certificates	1,063,907	611,718
Amount	8,145,778	8,169,696
Certificate accounts of $250,000 or more	348,200	346,900
Term certificates outstanding, scheduled maturities
2024	898,996
2025	136,462
2026	14,405
2027	6,158
2028	5,854
Thereafter	2,032
Total	1,063,907
Overdrawn deposit accounts classified as loans	3,900	1,500
Interest expense on deposit liabilities by type of deposit
Time certificates	31,366	5,372	$ 3,805
Savings	2,367	860	802
Money market	8,669	330	132
Interest-bearing checking	6,503	765	242
Interest expense on deposit liabilities	$ 48,905	$ 7,327	$ 4,981

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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No definition available.

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- Definition

Overdrawn Deposit Accounts

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- Definition

Weighted Average Rate Domestic Deposit, Checking, Noninterest-Bearing

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Weighted Average Rate Domestic Deposit, Commercial Checking

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- Definition

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
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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Interest expense incurred on all money market deposits.

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Interest expense incurred on all savings account deposits.

+ References

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

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

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

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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).

+ References

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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
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481047/942-405-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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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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No definition available.

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

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No definition available.

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The weighted average interest rate for domestic checking deposit liabilities.

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No definition available.

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

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No definition available.

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The weighted average interest rate for domestic savings deposit liabilities.

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No definition available.

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