Electric Operating Revenues - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Jan. 01, 2019
Disaggregation of Revenue [Line Items]
Other receivables, allowance for credit loss	$ 0	$ 0
Capitalized contract cost, amortization period			5 years
Contract assets	32,000,000	22,100,000
PNM
Disaggregation of Revenue [Line Items]
Contract with customers, net	$ 94,300,000	$ 93,600,000

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