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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 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	$ 28,378	$ 26,150	$ 56,071	$ 52,375
Services billings: \| PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	10,252	10,135	20,556	20,500
Services billings: \| PNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	123	94	216	212
Services billings: \| TNMP to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	35	12	71	24
Services billings: \| PNMR to NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	81	55	145	110
Renewable energy purchases: \| PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	3,801	3,504	6,422	6,089
Interconnection and facility study billings: \| PNM from NMRD
Related Party Transaction [Line Items]
Amount of related party transaction	0	0	0	0
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	2	0	9	0
Interest billings: \| PNMR to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	72	0	117	0
Interest billings: \| PNM to PNMR
Related Party Transaction [Line Items]
Amount of related party transaction	47	36	70	72
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