Bank segment (HEI only) - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 207	$ (59)	$ (137)
Not Designated as Hedging Instrument
Derivative instrument
Asset derivative	300	91
Liability derivative	45	43
Interest Rate Lock Commitments
Derivative instrument
Notional amount	23,171	10,180
Fair value	297	91
Interest Rate Lock Commitments \| Not Designated as Hedging Instrument
Derivative instrument
Asset derivative	297	91
Liability derivative	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	206	(40)	(290)
Forward commitments
Derivative instrument
Notional amount	29,383	10,132
Fair value	(42)	(43)
Forward commitments \| Not Designated as Hedging Instrument
Derivative instrument
Asset derivative	3	0
Liability derivative	45	43
Forward commitments \| Not Designated as Hedging Instrument \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 1	$ (19)	$ 153

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.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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