Regulatory and Rate Matters - Battery Energy Storage System Certificate of Public Convenience and Necessity ("CCN") (Details) - PNM $ in Millions			3 Months Ended
Oct. 25, 2023 batteryStorageAgreement	May 03, 2023 USD ($) MW	Dec. 31, 2022 batteryStorageAgreement
Public Utilities, General Disclosures [Line Items]
Number of battery storage agreements \| batteryStorageAgreement	3		2
Battery energy storage systems (megawatts) \| MW		6
Battery energy storage system, costs \| $		$ 25.8

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