Public Utilities, Commitments And Contingencies [Line Items]

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Public Utilities, Energy Efficiency And Load Management Programs Additional Incentive Targeted Energy Savings

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Public Utilities, Energy Efficiency And Load Management Programs Profit Incentive

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- Definition

Public Utilities, Energy Efficiency And Load Management Programs Targeted Energy Savings

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Public Utilities, Excess Return On Jurisdictional Equity That Would Require Refund

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Public Utilities, Frequency of IRP Filings

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Public Utilities, Integrated Resource Plan, Action Plan, Period

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Public Utilities, Number of Mega Watts of Solar Photovoltaic Capacity

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Public Utilities, Number of Mega Watts of Solar Photovoltaic Capacity, Current Output

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Public Utilities, Number of Mega Watts of Wind Energy Capacity

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Public Utilities, Planning Period Covered of IRP

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Public Utilities, Profit Incentive Sliding Scale Multiplier

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- Definition

Public Utilities, Program Costs Related To Energy Efficiency, in Year Four

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Public Utilities, Program Costs Related To Energy Efficiency, in Year Three

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Public Utilities, Program Costs Related To Energy Efficiency, in Year Two

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- Definition

Public Utilities, Reasonable Cost Threshold In Megawatts Per Hour

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Public Utilities, Renewable Energy Procurement Plan, Proposed Recovery, Amount

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Public Utilities, Revenue From Renewable Energy Rider

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Public Utilities, Solar generation capacity in Megawatts

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Regulatory and Rate Matters - PNM (Details) $ in Millions					3 Months Ended
Regulatory and Rate Matters - PNM (Details) $ in Millions	Jan. 01, 2022 USD ($)	Apr. 15, 2021 USD ($) GWh	Jan. 29, 2021	Apr. 15, 2020 USD ($) MMBTU	Mar. 31, 2022 USD ($) $ / MWh MW	Mar. 31, 2021 USD ($)	Jul. 29, 2020 MW
Public Utilities, Commitments And Contingencies [Line Items]
Excess return on jurisdictional equity that would require refund					0.50%
PNM
Public Utilities, Commitments And Contingencies [Line Items]
Solar generation capacity (in megawatts)							650
Renewable Portfolio Standard \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts of Solar PV facilities					158
Current output in the geothermal facility (in megawatts)					11
Solar generation capacity (in megawatts)					211.8
Energy Efficiency and Load Management Program \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Energy efficiency and load management programs targeted energy savings (in Gigawatts) \| MMBTU				94
Program costs related to energy efficiency, in year two \| $				$ 31.4
Program costs related to energy efficiency, in year three \| $				31.0
Program costs related to energy efficiency, in year four \| $				$ 29.6
Integrated Resource Plan, 2011 \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Frequency of IRP filings					3 years
Planning period covered of IRP					20 years
Integrated Resource Plan, 2020 \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Planning period covered of IRP			20 years
NMPRC
Public Utilities, Commitments And Contingencies [Line Items]
Action plan, covered period					4 years
NMPRC \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Proposed revision to rider that will allow for recovery \| $	$ 66.9
NMPRC \| Renewable Energy Rider \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Recorded revenues from renewable rider \| $					$ 14.5	$ 15.9
Maximum \| Renewable Portfolio Standard \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Reasonable cost threshold in megawatts per hour \| $ / MWh					60
Minimum \| Renewable Portfolio Standard \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Profit incentive sliding scale multiplier				0.071
Energy efficiency and load management programs targeted energy savings (in Gigawatts) \| MMBTU				80
New Mexico Wind \| Renewable Portfolio Standard 2014 \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy					200
Red Mesa Wind \| Renewable Portfolio Standard 2014 \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy					102
La Joya Wind \| Renewable Portfolio Standard \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Number of megawatts for wind energy					140
Disincentives and Incentives Added \| 2020 Energy Efficiency Annual Report \| PNM
Public Utilities, Commitments And Contingencies [Line Items]
Energy efficiency and load management programs additional incentive targeted energy savings (in Gigawatts) \| GWh		87
Energy efficiency and load management programs \| $		$ 0.8