Bank segment (HEI only) - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ (3,409)	$ 3,781	$ 207
Not Designated as Hedging Instrument
Derivative instrument
Asset derivatives	638	4,536
Liability derivatives	11	500
Interest rate lock commitments
Derivative instrument
Notional amount	39,377	120,980
Fair value	638	4,536
Interest rate lock commitments \| Not Designated as Hedging Instrument
Derivative instrument
Asset derivatives	638	4,536
Liability derivatives	0	0
Interest rate lock commitments \| Not Designated as Hedging Instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	(3,898)	4,239	206
Forward commitments
Derivative instrument
Notional amount	38,000	100,500
Fair value	(11)	(500)
Forward commitments \| Not Designated as Hedging Instrument
Derivative instrument
Asset derivatives	0	0
Liability derivatives	11	500
Forward commitments \| Not Designated as Hedging Instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 489	$ (458)	$ 1

Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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