XML 93 R77.htm IDEA: XBRL DOCUMENT
v3.23.2

Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Pension Plan | PNM |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer |  |  | $ 0 | $ 0
Estimated employer contributions for remainder of fiscal year through year four | $ 0 |  | 0 |
Estimated future contributions, year five | 400,000 |  | $ 400,000 |
Pension Plan | PNM | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 5.70% |
Pension Plan | Texas-New Mexico Power Company |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer |  |  | $ 0 | 0
Estimated employer contributions for remainder of fiscal year through year four | 0 |  | $ 0 |
Pension Plan | Texas-New Mexico Power Company | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Assumptions used calculating net periodic benefit cost, discount rate |  |  | 5.80% |
OPEB Plan | PNM |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer |  |  | $ 0 | 0
Disbursements by employer | 100,000 | $ 900,000 | 100,000 | 1,800,000
Disbursements by employer, year one through four |  |  | 9,000,000 |
Estimated disbursement by employer, current year |  |  | 200,000 |
OPEB Plan | Texas-New Mexico Power Company |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer | 0 | 0 | 0 | 0
Disbursements by employer, year one through four |  |  | 0 |
Executive Retirement Program | PNM |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer | 200,000 | 300,000 | 600,000 | 600,000
Disbursements by employer, year one through four |  |  | 4,500,000 |
Estimated disbursement by employer, current year |  |  | 1,300,000 |
Executive Retirement Program | Texas-New Mexico Power Company |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Disbursements by employer, year one through four |  |  | 200,000 |
Estimated disbursement by employer, current year |  |  | 100,000 |
Executive Retirement Program | Texas-New Mexico Power Company | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions by employer | $ 0 | $ 0 | $ 0 | $ 0

X
- Definition Defined Benefit Plan, Estimated Future Contributions, Year Five + References No definition available. + Details
Name: | pnm_DefinedBenefitPlanEstimatedFutureContributionsYearFive
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Defined Benefit Plan, Estimated Future Employer Contributions Remainder of Fiscal Year Through Year Four + References No definition available. + Details
Name: | pnm_DefinedBenefitPlanEstimatedFutureEmployerContributionsRemainderOfFiscalYearThroughYearFour
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Defined Benefit Plan, Estimated Future Employer Disbursements, Year One Through Four + References No definition available. + Details
Name: | pnm_DefinedBenefitPlanEstimatedFutureEmployerDisbursementsYearOneThroughFour
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Defined Benefit Plan, Plan Assets, Disbursements By Employer + References No definition available. + Details
Name: | pnm_DefinedBenefitPlanPlanAssetsDisbursementsByEmployer
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Defined Benefit Plan, Plan Assets, Estimated Disbursement By Employer, Current Year + References No definition available. + Details
Name: | pnm_DefinedBenefitPlanPlanAssetsEstimatedDisbursementByEmployerCurrentYear
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
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: | srt_RangeAxis=srt_MaximumMember
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_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |