Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Regulatory Assets
Current	$ 20,265	$ 14,785
Non-Current	846,686	514,258
Regulatory Liabilities
Current	(17,002)	(8,316)
Non-Current	(755,202)	(841,393)
Public Service Company of New Mexico
Regulatory Assets
Current	18,333	8,721
Non-Current	763,941	428,981
Total regulatory assets	782,274	437,702
Regulatory Liabilities
Current	(7,913)	(8,316)
Non-Current	(556,989)	(653,830)
Total regulatory liabilities	(564,902)	(662,146)
Public Service Company of New Mexico | Renewable energy rider, including excess return
Regulatory Liabilities
Current	(5,076)	(5,989)
Public Service Company of New Mexico | Energy efficiency costs
Regulatory Liabilities
Current	(2,837)	(2,327)
Public Service Company of New Mexico | Transmission cost recovery factor
Regulatory Liabilities
Current	0	0
Public Service Company of New Mexico | Cost of removal
Regulatory Liabilities
Non-Current	(238,903)	(294,193)
Public Service Company of New Mexico | Deferred income taxes
Regulatory Liabilities
Non-Current	(301,493)	(321,976)
Public Service Company of New Mexico | PVNGS ARO
Regulatory Liabilities
Non-Current	0	(1,215)
Public Service Company of New Mexico | Renewable energy tax benefits
Regulatory Liabilities
Non-Current	(15,610)	(16,756)
Public Service Company of New Mexico | Accelerated depreciation SNCRs
Regulatory Liabilities
Non-Current	0	(16,331)
Public Service Company of New Mexico | Pension and OPEB
Regulatory Liabilities
Non-Current	0	(2,376)
Public Service Company of New Mexico | COVID-19 cost savings
Regulatory Liabilities
Non-Current	(900)	(900)
Public Service Company of New Mexico | Other
Regulatory Liabilities
Non-Current	(83)	(83)
Public Service Company of New Mexico | FPPAC
Regulatory Assets
Current	8,904	7,130
Public Service Company of New Mexico | NMPRC hedging plan
Regulatory Assets
Current	9,429	1,591
Public Service Company of New Mexico | Transmission cost recovery factor
Regulatory Assets
Current	0	0
Public Service Company of New Mexico | Energy efficiency costs
Regulatory Assets
Current	0	0
Public Service Company of New Mexico | SJGS - ETA
Regulatory Assets
Non-Current	343,238	51,975
Public Service Company of New Mexico | SJGS - Non-ETA
Regulatory Assets
Non-Current	26,296	43
Public Service Company of New Mexico | Shutdown of SJGS Units 2 and 3
Regulatory Assets
Non-Current	94,677	100,954
Public Service Company of New Mexico | SJGS replacement resources
Regulatory Assets
Non-Current	8,312	8,269
Public Service Company of New Mexico | EIM
Regulatory Assets
Non-Current	13,102	7,028
Public Service Company of New Mexico | Loss on reacquired debt
Regulatory Assets
Non-Current	15,323	17,249
Public Service Company of New Mexico | Pension and OPEB
Regulatory Assets
Non-Current	187,182	165,006
Public Service Company of New Mexico | Deferred income taxes
Regulatory Assets
Non-Current	67,621	68,687
Public Service Company of New Mexico | AMS surcharge
Regulatory Assets
Non-Current	0	0
Public Service Company of New Mexico | AMS retirement and other costs
Regulatory Assets
Non-Current	0	0
Public Service Company of New Mexico | Deferred COVID-19 costs
Regulatory Assets
Non-Current	5,664	6,896
Public Service Company of New Mexico | Other
Regulatory Assets
Non-Current	2,526	2,874
Texas-New Mexico Power Company
Regulatory Assets
Current	1,932	6,064
Non-Current	82,745	85,277
Total regulatory assets	84,677	91,341
Regulatory Liabilities
Current	(9,089)	0
Non-Current	(198,213)	(187,563)
Total regulatory liabilities	(207,302)	(187,563)
Texas-New Mexico Power Company | Renewable energy rider, including excess return
Regulatory Liabilities
Current	0	0
Texas-New Mexico Power Company | Energy efficiency costs
Regulatory Liabilities
Current	0	0
Texas-New Mexico Power Company | Transmission cost recovery factor
Regulatory Liabilities
Current	(9,089)	0
Texas-New Mexico Power Company | Cost of removal
Regulatory Liabilities
Non-Current	(97,030)	(73,029)
Texas-New Mexico Power Company | Deferred income taxes
Regulatory Liabilities
Non-Current	(94,994)	(107,250)
Texas-New Mexico Power Company | PVNGS ARO
Regulatory Liabilities
Non-Current	0	0
Texas-New Mexico Power Company | Renewable energy tax benefits
Regulatory Liabilities
Non-Current	0	0
Texas-New Mexico Power Company | Accelerated depreciation SNCRs
Regulatory Liabilities
Non-Current	0	0
Texas-New Mexico Power Company | Pension and OPEB
Regulatory Liabilities
Non-Current	(4,518)	(6,099)
Texas-New Mexico Power Company | COVID-19 cost savings
Regulatory Liabilities
Non-Current	0	0
Texas-New Mexico Power Company | Other
Regulatory Liabilities
Non-Current	(1,671)	(1,185)
Texas-New Mexico Power Company | FPPAC
Regulatory Assets
Current	0	0
Texas-New Mexico Power Company | NMPRC hedging plan
Regulatory Assets
Current	0	0
Texas-New Mexico Power Company | Transmission cost recovery factor
Regulatory Assets
Current	0	3,906
Texas-New Mexico Power Company | Energy efficiency costs
Regulatory Assets
Current	1,932	2,158
Texas-New Mexico Power Company | SJGS - ETA
Regulatory Assets
Non-Current	0	0
Texas-New Mexico Power Company | SJGS - Non-ETA
Regulatory Assets
Non-Current	0	0
Texas-New Mexico Power Company | Shutdown of SJGS Units 2 and 3
Regulatory Assets
Non-Current	0	0
Texas-New Mexico Power Company | SJGS replacement resources
Regulatory Assets
Non-Current	0	0
Texas-New Mexico Power Company | EIM
Regulatory Assets
Non-Current	0	0
Texas-New Mexico Power Company | Loss on reacquired debt
Regulatory Assets
Non-Current	26,317	27,615
Texas-New Mexico Power Company | Pension and OPEB
Regulatory Assets
Non-Current	21,558	17,924
Texas-New Mexico Power Company | Deferred income taxes
Regulatory Assets
Non-Current	9,193	9,505
Texas-New Mexico Power Company | AMS surcharge
Regulatory Assets
Non-Current	6,254	12,507
Texas-New Mexico Power Company | AMS retirement and other costs
Regulatory Assets
Non-Current	12,591	12,286
Texas-New Mexico Power Company | Deferred COVID-19 costs
Regulatory Assets
Non-Current	1,053	0
Texas-New Mexico Power Company | Other
Regulatory Assets
Non-Current	$ 5,779	$ 5,440