XML 82 R65.htm IDEA: XBRL DOCUMENT
v3.20.2

Regulatory and Rate Matters - Transmission Cost of Service Rates (Details) - PUCT - TNMP - USD ($) $ in Millions | Oct. 07, 2020 | Mar. 27, 2020 | Sep. 19, 2019 | Mar. 21, 2019
--- | --- | --- | --- | ---
Public Utilities, General Disclosures [Line Items] |  |  |  |
Approved Increase in Rate Base |  | $ 59.2 | $ 21.9 | $ 111.8
Annual Increase in Revenue |  | $ 7.8 | $ 3.3 | $ 14.3
Subsequent event |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |
Approved Increase in Rate Base | $ 10.8 |  |  |
Annual Increase in Revenue | $ 2.0 |  |  |

X
- Definition Public Utilities, Increase Annual Transmission Service Revenue + References No definition available. + Details
Name: | pnm_PublicUtilitiesIncreaseAnnualTransmissionServiceRevenue
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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 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
- Details
Name: | us-gaap_RegulatoryAgencyAxis=pnm_PUCTMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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: |