The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
PNMR Development
Related Party Transaction [Line Items]
Ownership	50.00%		50.00%
Services billings: \| PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	$ 26,281	$ 23,617	$ 82,352	$ 75,992
Services billings: \| PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	9,554	9,187	30,110	29,687
Services billings: \| PNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	107	107	322	319
Services billings: \| TNMP to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	35	0	106	24
Services billings: \| PNMR to NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	81	55	226	165
Renewable energy purchases: \| PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	3,221	3,384	9,642	9,473
Interconnection and facility study billings: \| PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	0	225	0	225
Interconnection and facility study billings: \| PNM to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	0	0	0	0
Interconnection and facility study billings: \| NMRD to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	0	0	0	1,276
Interest billings: \| PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	4	0	13	0
Interest billings: \| PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	50	0	166	0
Interest billings: \| PNM to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	73	36	143	108
Income tax sharing payments: \| PNMR to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	0	0	0	0
Income tax sharing payments: \| TNMP to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	$ 0	$ 0	$ 0	$ 0