Name:	he_AggregateofPowerPurchaseCapacityExcludingAgreementwithSmallerIndependentPowerProducers
Namespace Prefix:	he_
Data Type:	num:powerItemType
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Long Term Purchase Commitment, Arbitration, Additional Capacity Requirement

No definition available.

Name:	he_LongTermPurchaseCommitmentArbitrationAdditionalCapacityRequirement
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Data Type:	num:powerItemType
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Long-term Purchase Commitment, Minimum Power Volume Required

No definition available.

Name:	he_LongtermPurchaseCommitmentMinimumPowerVolumeRequired
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Represents the number of firm power purchase agreements entered into, by the company.

No definition available.

Name:	he_NumberOfPowerPurchaseAgreements
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-- None. No documentation exists for this element. --

No definition available.

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Utilities Expected Fixed Capacity Charges, After Five Through Fifteen Years

No definition available.

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Utilities Expected Fixed Capacity Charges, Year Five

No definition available.

Name:	he_UtilitiesExpectedFixedCapacityChargesYearFive
Namespace Prefix:	he_
Data Type:	xbrli:monetaryItemType
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Utilities Expected Fixed Capacity Charges, Year Four

No definition available.

Name:	he_UtilitiesExpectedFixedCapacityChargesYearFour
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Utilities Expected Fixed Capacity Charges, Year One

No definition available.

Name:	he_UtilitiesExpectedFixedCapacityChargesYearOne
Namespace Prefix:	he_
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Utilities Expected Fixed Capacity Charges, Year Three

No definition available.

Name:	he_UtilitiesExpectedFixedCapacityChargesYearThree
Namespace Prefix:	he_
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Utilities Expected Fixed Capacity Charges, Year Two

No definition available.

Name:	he_UtilitiesExpectedFixedCapacityChargesYearTwo
Namespace Prefix:	he_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_LongtermPurchaseCommitmentPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of operating expense for purchased power of regulated operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(b))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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