Bank segment (HEI only) - Deposit Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Weighted-average stated rate
Savings	0.03%	0.03%
Checking, interest-bearing	0.02%	0.02%
Checking, Noninterest-bearing	0.00%	0.00%
Commercial checking	0.00%	0.00%
Money market	0.06%	0.09%
Time certificates	0.67%	0.99%
Weighted-average stated rate	0.05%	0.09%
Deposit liabilities
Savings	$ 3,234,646	$ 2,873,727
Checking
Interest-bearing	1,344,049	1,196,675
Noninterest-bearing	1,472,727	1,329,264
Commercial checking	1,503,905	1,269,236
Money market	192,909	169,225
Time certificates	423,976	548,830
Amount	8,172,212	7,386,957
Certificate accounts of $250,000 or more	87,600	121,300
Term certificates outstanding, scheduled maturities
2022	275,702
2023	60,049
2024	47,248
2025	24,278
2026	13,736
Thereafter	2,963
Total	423,976
Overdrawn deposit accounts classified as loans	1,300	1,000
Interest expense on deposit liabilities by type of deposit
Time certificates	3,805	7,944	$ 12,675
Savings	802	1,774	1,904
Money market	132	465	953
Interest-bearing checking	242	471	1,298
Interest expense on deposit liabilities	$ 4,981	$ 10,654	$ 16,830

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 http://asc.fasb.org/extlink&oid=120398452&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.

+ References

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 http://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)
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-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)
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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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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
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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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