XML 129 R104.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Commitments and Contingencies - Right-of-Way, Complaints, and Navajo National Allottee Matters (Details) $ in Millions |  | 3 Months Ended |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 04, 2016 | Dec. 31, 2017 USD ($) | Dec. 31, 2018 USD ($) | Oct. 31, 2018 USD ($) | Nov. 20, 2017 Allotment_Parcel | Dec. 01, 2015 Allotment_Parcel | Jul. 13, 2015 a | Jan. 22, 2015 Allotment_Parcel | Apr. 02, 2014 landowner Allotment_Parcel | Feb. 27, 2014 lawsuit | Sep. 30, 2012 landowner
First Choice |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |
Additional tax due plus penalties and interest | $ |  | $ 5.0 |  |  |  |  |  |  |  |  |
Navajo Nation Allottee Matters | Public Service Company of New Mexico |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of landowners claiming to be Navajo allottees (in landowners) | landowner |  |  |  |  |  |  |  |  | 43 |  | 43
Number of allotments where landowners are revoking rights of way renewal consents (in allotment parcels) |  |  |  |  |  |  |  |  | 6 |  |
Allotments with right-of-way renewals not previously contested (in allotment parcels) |  |  |  |  |  |  |  | 10 |  |  |
Acres of land at issue (in acres) | a |  |  |  |  |  |  | 15.49 |  |  |  |
Number of allotment parcels that cannot be condemned |  |  |  |  | 2 | 2 |  |  |  |  |
Number of allotment parcels at issue |  |  |  |  |  | 5 |  |  |  |  |
Pending Litigation |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of claims (in lawsuits) | lawsuit |  |  |  |  |  |  |  |  |  | 2 |
Written notification requirement to terminate agreement, minimum period | 30 days |  |  |  |  |  |  |  |  |  |
Settled Litigation |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of claims (in lawsuits) | lawsuit |  |  |  |  |  |  |  |  |  | 1 |
State and Local Jurisdiction | First Choice |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |
Sales and use tax audit | $ |  |  | $ 1.4 | $ 0.9 |  |  |  |  |  |  |

X
- Definition Additional Tax Due Plus Penalties and Interest + References No definition available. + Details
Name: | pnm_AdditionalTaxDuePlusPenaltiesandInterest
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Loss Contingency, Written Notification to Terminate Agreement, Minimum Period of Time Required + References No definition available. + Details
Name: | pnm_LossContingencyWrittenNotificationtoTerminateAgreementMinimumPeriodofTimeRequired
Namespace Prefix: | pnm_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of allotment parcels' at issue + References No definition available. + Details
Name: | pnm_Numberofallotmentparcelsatissue
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of allotment parcels' at issue, Not to be condemned + References No definition available. + Details
Name: | pnm_NumberofallotmentparcelsatissueNottobecondemned
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of allotments, Previously contested rights of way renewal consents + References No definition available. + Details
Name: | pnm_NumberofallotmentsPreviouslycontestedrightsofwayrenewalconsents
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of allotments where landowners are revoking rights of way renewal consents + References No definition available. + Details
Name: | pnm_Numberofallotmentswherelandownersarerevokingrightsofwayrenewalconsents
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of landowners claiming to be Navajo allottees + References No definition available. + Details
Name: | pnm_NumberoflandownersclaimingtobeNavajoallottees
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Area of land held. + References No definition available. + Details
Name: | us-gaap_AreaOfLand
Namespace Prefix: | us-gaap_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
Name: | us-gaap_IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=pnm_NavajoNationAllotteeMattersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LitigationStatusAxis=us-gaap_SettledLitigationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |