Estimated Project Costs

No definition available.

Name:	pnm_EstimatedProjectCosts
Namespace Prefix:	pnm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Public Utilities, Megawatts Purchase Power Agreements Period

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesMegawattsPurchasePowerAgreementsPeriod
Namespace Prefix:	pnm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Public Utilities, Number Of Megawatts Available In Purchase Power Agreement

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesNumberOfMegawattsAvailableInPurchasePowerAgreement
Namespace Prefix:	pnm_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Public Utilities, Number Of Megawatts Batteries To Be Constructed

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesNumberOfMegawattsBatteriesToBeConstructed
Namespace Prefix:	pnm_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Public Utilities, Number Of Megawatts of Energy Storage

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesNumberOfMegawattsOfEnergyStorage
Namespace Prefix:	pnm_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Public Utilities, Number Of Megawatts Purchase Power Agreements

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesNumberOfMegawattsPurchasePowerAgreements
Namespace Prefix:	pnm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Sites

+ References

No definition available.

+ Details

Name:	pnm_PublicUtilitiesNumberOfSites
Namespace Prefix:	pnm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- 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

- Details

Name:	dei_LegalEntityAxis=pnm_PublicServiceCompanyOfNewMexicoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=pnm_OteroSanMiguelAndLunaCountiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=pnm_ValenciaCountyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_PowerPurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_EnergyStorageAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Regulatory and Rate Matters - Meta Platforms Inc. Data Center - Phase IV, BESS Project (Details) $ in Millions	Aug. 06, 2025 USD ($) MW facility	Jun. 13, 2025 MW power_purchase_agreement energy_storage_agreement	Nov. 22, 2024 MW
Public Utilities, General Disclosures [Line Items]
Estimated project costs \| $	$ 78.7
Public Service Company of New Mexico
Public Utilities, General Disclosures [Line Items]
Megawatts of energy storage	30
Megawatts batteries to be constructed	6
Public Service Company of New Mexico \| Otero, San Miguel and Luna Counties
Public Utilities, General Disclosures [Line Items]
Number of sites \| facility	5
Public Service Company of New Mexico \| Valencia County
Public Utilities, General Disclosures [Line Items]
Number of sites \| facility	2
Power Purchase Agreement \| Public Service Company of New Mexico
Public Utilities, General Disclosures [Line Items]
Number of megawatts purchase power agreements (in megawatts) \| power_purchase_agreement		3
Megawatts purchase power agreements period		20 years
Number of megawatts available in purchase power agreement (in megawatts)		290
Energy Storage Agreements \| Public Service Company of New Mexico
Public Utilities, General Disclosures [Line Items]
Number of megawatts purchase power agreements (in megawatts)		3	2
Megawatts purchase power agreements period		20 years
Number of megawatts available in purchase power agreement (in megawatts)		268	150