XML 91 R57.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Electric utility segment - Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Regulatory assets |  |
Regulatory assets | $ 869,297 | $ 957,451
Regulatory liabilities |  |
Regulatory liabilities | $ 880,770 | 410,693
Minimum | Income taxes |  |
Regulatory liabilities |  |
Authorized amortization or recovery periods | 1 year |
Maximum | Income taxes |  |
Regulatory liabilities |  |
Authorized amortization or recovery periods | 55 years |
Hawaiian Electric Company, Inc. and Subsidiaries |  |
Regulatory assets |  |
Regulatory assets | $ 869,297 | 957,451
Regulatory liabilities |  |
Regulatory liabilities | 880,770 | 410,693
Hawaiian Electric Company, Inc. and Subsidiaries | Cost of removal in excess of salvage value |  |
Regulatory liabilities |  |
Regulatory liabilities | 453,986 | 394,072
Hawaiian Electric Company, Inc. and Subsidiaries | Income taxes |  |
Regulatory liabilities |  |
Regulatory liabilities | 406,324 | 0
Hawaiian Electric Company, Inc. and Subsidiaries | Retirement benefit plans, regulatory liabilities |  |
Regulatory liabilities |  |
Regulatory liabilities | $ 9,961 | 10,824
Authorized amortization or recovery periods | 5 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Other, regulatory liabilities |  |
Regulatory liabilities |  |
Regulatory liabilities | $ 10,499 | 5,797
Authorized amortization or recovery periods | 5 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Minimum | Cost of removal in excess of salvage value |  |
Regulatory liabilities |  |
Authorized amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Minimum | Other, regulatory liabilities |  |
Regulatory liabilities |  |
Remaining amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Maximum | Cost of removal in excess of salvage value |  |
Regulatory liabilities |  |
Authorized amortization or recovery periods | 60 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Maximum | Other, regulatory liabilities |  |
Regulatory liabilities |  |
Remaining amortization or recovery periods | 2 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Current assets |  |
Regulatory assets |  |
Regulatory assets | $ 88,390 | 66,032
Hawaiian Electric Company, Inc. and Subsidiaries | Long-term assets |  |
Regulatory assets |  |
Regulatory assets | 780,907 | 891,419
Hawaiian Electric Company, Inc. and Subsidiaries | Current liabilities |  |
Regulatory liabilities |  |
Regulatory liabilities | 3,401 | 3,762
Hawaiian Electric Company, Inc. and Subsidiaries | Long-term liabilities |  |
Regulatory liabilities |  |
Regulatory liabilities | 877,369 | 406,931
Hawaiian Electric Company, Inc. and Subsidiaries | Retirement benefit plans, regulatory assets |  |
Regulatory assets |  |
Regulatory assets | 637,204 | 745,367
Hawaiian Electric Company, Inc. and Subsidiaries | Income taxes |  |
Regulatory assets |  |
Regulatory assets | $ 118,201 | 90,100
Hawaiian Electric Company, Inc. and Subsidiaries | Income taxes | Minimum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Income taxes | Maximum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 55 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Decoupling revenue balancing account |  |
Regulatory assets |  |
Regulatory assets | $ 64,087 | 73,485
Hawaiian Electric Company, Inc. and Subsidiaries | Decoupling revenue balancing account | Minimum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Decoupling revenue balancing account | Maximum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 2 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Unamortized expense and premiums on retired debt and equity issuances |  |
Regulatory assets |  |
Regulatory assets | $ 11,993 | 12,299
Hawaiian Electric Company, Inc. and Subsidiaries | Unamortized expense and premiums on retired debt and equity issuances | Minimum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 19 years |
Remaining amortization or recovery periods | 6 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Unamortized expense and premiums on retired debt and equity issuances | Maximum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 30 years |
Remaining amortization or recovery periods | 18 years |
Hawaiian Electric Company, Inc. and Subsidiaries | Vacation earned, but not yet taken |  |
Regulatory assets |  |
Regulatory assets | $ 11,224 | 10,970
Authorized amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Other, regulatory assets |  |
Regulatory assets |  |
Regulatory assets | $ 26,588 | $ 25,230
Hawaiian Electric Company, Inc. and Subsidiaries | Other, regulatory assets | Minimum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 1 year |
Remaining amortization or recovery periods | 1 year |
Hawaiian Electric Company, Inc. and Subsidiaries | Other, regulatory assets | Maximum |  |
Regulatory assets |  |
Authorized amortization or recovery periods | 50 years |
Remaining amortization or recovery periods | 46 years |

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | he_RegulatoryAssets1Abstract
Namespace Prefix: | he_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | he_RegulatoryLiabilities1Abstract
Namespace Prefix: | he_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The remaining amortization period for the individual regulatory liability in a schedule of regulatory liabilities. + References No definition available. + Details
Name: | he_RegulatoryLiabilityRemainingAmortizationOrRecoveryPeriod
Namespace Prefix: | he_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amortization period for recovery of the individual regulatory noncurrent asset in a schedule of regulatory noncurrent assets. + References No definition available. + Details
Name: | he_RegulatoryNoncurrentAssetAmortizationPeriodDuration
Namespace Prefix: | he_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The remaining amortization period for recovery of the individual regulatory noncurrent asset in a schedule of regulatory noncurrent assets. + References No definition available. + Details
Name: | he_RegulatoryNoncurrentAssetRemainingAmortizationOrRecoveryPeriod
Namespace Prefix: | he_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amortization period for recovery of the individual regulatory noncurrent liability in a schedule of regulatory noncurrent liabilities. + References No definition available. + Details
Name: | he_RegulatoryNoncurrentLiabilityAmortizationPeriodDuration
Namespace Prefix: | he_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 405 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
Name: | us-gaap_RegulatoryLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_DeferredIncomeTaxChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=he_HawaiianElectricCompanyAndSubsidiariesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=he_CostOfRemovalInExcessOfSalvageValueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_PensionCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=he_OtherRegulatoryLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=he_CurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=he_LongTermAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=he_CurrentLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=he_LongtermLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=he_RetirementBenefitCostAssetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_DeferredIncomeTaxChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=he_DecouplingRevenueBalancingAccountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=he_UnamortizedExpenseAndPremiumsOnRetiredDebtAndEquityIssuancesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_RecoverableVacationPayMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=he_OtherRegulatoryAssetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |