XML 83 R67.htm IDEA: XBRL DOCUMENT
v3.21.2

Regulatory and Rate Matters - TNMP Narrative (Details) - TNMP $ in Millions |  |  |  |  |  | 1 Months Ended |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 01, 2021 USD ($) | Apr. 05, 2021 USD ($) | Jun. 26, 2020 USD ($) | Apr. 14, 2020 USD ($) | Apr. 06, 2020 USD ($) | Oct. 31, 2019 USD ($) | Aug. 31, 2019 USD ($) | Jul. 28, 2021 USD ($) | Jun. 30, 2021 USD ($) | May 27, 2021 USD ($) | Mar. 01, 2021 USD ($) | Dec. 31, 2020 USD ($) | Oct. 02, 2020 USD ($) | Mar. 30, 2020 MWh | Mar. 01, 2020 USD ($) | Dec. 31, 2019 USD ($)
Public Utilities, Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested increase in annual distribution revenue |  | $ 14.0 |  |  | $ 14.7 |  |  |  |  |  |  |  |  |  |  |
Incremental distribution investments |  |  |  |  | $ 149.2 |  |  |  |  |  |  |  |  |  |  |
Annual distribution revenue requirement |  |  | $ 14.3 |  |  |  |  |  |  |  |  |  |  |  |  |
Increase in revenue base rate |  | $ 104.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Energy efficiency cost recovery, requested change amount |  |  |  |  |  |  |  |  |  | $ 7.2 | $ 5.9 |  |  |  | $ 5.9 |
Energy efficiency cost recovery, requested bonus |  |  |  |  |  |  |  |  |  | $ 2.3 | $ 1.0 |  |  |  | $ 0.8 |
Rider charge from electricity relief program (per MWh) | MWh |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.33 |  |
Proceeds from short-term debt |  |  |  | $ 0.5 |  |  |  |  |  |  |  |  |  |  |  |
Public utilities, estimate of possible upgrades |  |  |  |  |  |  |  |  |  |  |  |  | $ 46.0 |  |  |
Subsequent event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collection of increase in annual distribution revenues | $ 13.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Energy efficiency cost recovery, requested bonus |  |  |  |  |  |  |  | $ 2.3 |  |  |  |  |  |  |  |
COVID-19 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory liability |  |  |  |  |  |  |  |  |  |  |  | $ 0.1 |  |  |  |
Other COVID-19 related costs |  |  |  |  |  |  |  |  | $ 0.8 |  |  | $ 0.7 |  |  |  |
2018 TNMP Rate Case |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recovery of costs incurred |  |  |  |  |  | $ 3.3 | $ 3.8 |  |  |  |  |  |  |  |  |
Recovery costs collection period |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |
Write off of regulatory disallowance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.5

X
- Definition Energy Efficiency Cost Recovery Factor, Requested Change Amount + References No definition available. + Details
Name: | pnm_EnergyEfficiencyCostRecoveryFactorRequestedChangeAmount
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Energy Efficiency Cost Recovery Factor, Requested Performance Bonus + References No definition available. + Details
Name: | pnm_EnergyEfficiencyCostRecoveryFactorRequestedPerformanceBonus
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Other Deferred Costs, Gross, CARES Act + References No definition available. + Details
Name: | pnm_OtherDeferredCostsGrossCARESAct
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Annual Distribution Revenue Requirement + References No definition available. + Details
Name: | pnm_PublicUtilitiesAnnualDistributionRevenueRequirement
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Collection Of Increase In Annual Distribution Revenues + References No definition available. + Details
Name: | pnm_PublicUtilitiesCollectionOfIncreaseInAnnualDistributionRevenues
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Commitments And Contingencies [Line Items] + References No definition available. + Details
Name: | pnm_PublicUtilitiesCommitmentsAndContingenciesLineItems
Namespace Prefix: | pnm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public Utilities, Estimate Of Possible Upgrades + References No definition available. + Details
Name: | pnm_PublicUtilitiesEstimateOfPossibleUpgrades
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Public Utilities, Increase In Rate Base + References No definition available. + Details
Name: | pnm_PublicUtilitiesIncreaseInRateBase
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Incremental Distribution Investments + References No definition available. + Details
Name: | pnm_PublicUtilitiesIncrementalDistributionInvestments
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Public Utilities, Requested Increase Annual Distribution Revenue Requirement + References No definition available. + Details
Name: | pnm_PublicUtilitiesRequestedIncreaseAnnualDistributionRevenueRequirement
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Rider Charge From Electricity Relief Program + References No definition available. + Details
Name: | pnm_PublicUtilitiesRiderChargeFromElectricityReliefProgram
Namespace Prefix: | pnm_
Data Type: | dtr-types:energyItemType
Balance Type: | na
Period Type: | instant

X
- Definition Public Utilities, Write off Regulatory Disallowance + References No definition available. + Details
Name: | pnm_PublicUtilitiesWriteOffRegulatoryDisallowance
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromShortTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Return of or reimbursements received in relation to direct costs and expenses previously paid or incurred. + References 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) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 + Details
Name: | us-gaap_RecoveryOfDirectCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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://fasb.org/us-gaap/role/ref/legacyRef -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
- Definition Remaining recovery period of regulatory assets for which no return on investment during recovery period is provided, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 55 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123406419&loc=d3e44360-110383 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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_RemainingRecoveryPeriodOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=pnm_TexasNewMexicoPowerCompanyMember
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_UnusualOrInfrequentItemAxis=pnm_COVID19Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_A2018TNMPRateCaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |