XML 58 R46.htm IDEA: XBRL DOCUMENT
v3.20.2

Regulatory Matters: Rate Review (Details) $ in Thousands |  |  |  |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2022 | Sep. 11, 2020 USD ($) mi | Jun. 01, 2020 USD ($) mi | May 19, 2020 USD ($) | Feb. 01, 2019 USD ($) utility | Sep. 30, 2020 USD ($) | Sep. 30, 2020 USD ($) | Oct. 15, 2020 MW
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Income Tax Benefit from Relieved TCJA Related Liabilities |  |  |  |  |  | $ 3,500 | $ 4,000 |
Federal Energy Regulatory Commission (FERC) | Black Hills Wyoming and Wyoming Electric | Subsequent Event |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Number of Megawatts Capacity Purchased | MW |  |  |  |  |  |  |  | 60
Public Utilities Term of Power Purchase Agreement | 11 years |  |  |  |  |  |  |
Rate Review Filed with the Regulatory Agency | Colorado Public Utilities Commission (CPUC) | Black Hills Energy, Colorado Gas |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments | mi |  | 7,000 |  |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  | $ 13,500 |  |  | $ 2,500 |  |  |
Public Utilities, Requested Equity Capital Structure, Percentage |  | 50.00% |  |  |  |  |  |
Public Utilities, Requested Debt Capital Structure, Percentage |  | 50.00% |  |  |  |  |  |
Public Utilities, Requested Return on Equity, Percentage |  | 9.95% |  |  |  |  |  |
Public Utilities, Number of Gas Distribution Territories Consolidating | utility |  |  |  |  | 2 |  |  |
Public Utilities, Approved Rate Increase (Decrease), Amount |  |  |  | $ 600 |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  |  |  | 9.20% |  |  |  |
Rate Review Filed with the Regulatory Agency | Nebraska Publc Service Commission (NPSC) | Black Hills Energy, Nebraska Gas |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments | mi |  |  | 13,000 |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  | $ 17,300 |  |  |  |  |
Public Utilities, Requested Equity Capital Structure, Percentage |  |  | 50.00% |  |  |  |  |
Public Utilities, Requested Debt Capital Structure, Percentage |  |  | 50.00% |  |  |  |  |
Public Utilities, Requested Return on Equity, Percentage |  |  | 10.00% |  |  |  |  |
Public Utilities, State Statute Allows for Implementation of Interim Rates After Certain Number of Days Following Filing of Rate Review |  |  | 90 days |  |  |  |  |
System Safety and Integrity Rider Rate Review Filed with the Regulatory Agency | Colorado Public Utilities Commission (CPUC) | Black Hills Energy, Colorado Gas |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Public Utilities, Requested Term of Rate Recovery |  | 5 years |  |  |  |  |  |
System Safety and Integrity Rider Rate Review Filed with the Regulatory Agency | Nebraska Publc Service Commission (NPSC) | Black Hills Energy, Nebraska Gas |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |
Public Utilities, Requested Term of Rate Recovery |  |  | 5 years |  |  |  |  |

X
- Definition Income Tax Benefit from Relieved TCJA Related Liabilities + References No definition available. + Details
Name: | bkh_IncomeTaxBenefitFromRelievedTCJARelatedLiabilities
Namespace Prefix: | bkh_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of Megawatts Capacity Purchased + References No definition available. + Details
Name: | bkh_NumberOfMegawattsCapacityPurchased
Namespace Prefix: | bkh_
Data Type: | num:powerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments + References No definition available. + Details
Name: | bkh_PublicUtilitiesLengthOfNaturalGasPipelineToReceiveInfrastructureInvestments
Namespace Prefix: | bkh_
Data Type: | num:lengthItemType
Balance Type: | na
Period Type: | instant

X
- Definition Public Utilities, Number of Gas Distribution Territories Consolidating + References No definition available. + Details
Name: | bkh_PublicUtilitiesNumberofGasDistributionTerritoriesConsolidating
Namespace Prefix: | bkh_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Public Utilities, Requested Term of Rate Recovery + References No definition available. + Details
Name: | bkh_PublicUtilitiesRequestedTermOfRateRecovery
Namespace Prefix: | bkh_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public Utilities, State Statute Allows for Implementation of Interim Rates After Certain Number of Days Following Filing of Rate Review + References No definition available. + Details
Name: | bkh_PublicUtilitiesStateStatuteAllowsForImplementationOfInterimRatesAfterCertainNumberOfDaysFollowingFilingOfRateReview
Namespace Prefix: | bkh_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public Utilities Term of Power Purchase Agreement + References No definition available. + Details
Name: | bkh_PublicUtilitiesTermOfPowerPurchaseAgreement
Namespace Prefix: | bkh_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of public utility's approved return on equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_PublicUtilitiesGeneralDisclosuresLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of public utility's requested debt to capital, including debt and equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedDebtCapitalStructurePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of public utility's requested equity to capital, including debt and equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedEquityCapitalStructurePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of public utility's requested return on equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedReturnOnEquityPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=bkh_FederalEnergyRegulatoryCommissionFERCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=bkh_RateReviewFiledwiththeRegulatoryAgencyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=bkh_ColoradoPublicUtilitiesCommissionCPUCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=bkh_NebraskaPublcServiceCommissionNPSCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=bkh_SystemSafetyAndIntegrityRiderRateReviewFiledWithTheRegulatoryAgencyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |