Fair Value of Derivative and Other Financial Instruments - Schedule of Commodity Contract Volume Positions (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2023 MMBTU	Sep. 30, 2023 MWh	Dec. 31, 2023 MMBTU	Dec. 31, 2023 MWh
Commodity Contract \| Designated as hedging instrument \| PNM
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Economic Hedges (in mmbtu and mwh)	0	432,200	0	(15,360)

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.

No definition available.

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