Pension and Other Postretirement Benefits - Components of Net Periodic Benefit Cost (Income) Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Public Service Company of New Mexico | Pension Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 0	$ 0	$ 0
Interest cost	16,857	16,143	19,941
Expected return on plan assets	(28,563)	(28,531)	(29,453)
Amortization of net loss	15,794	18,166	17,860
Amortization of prior service cost	0	0	(554)
Net periodic benefit cost	4,088	5,778	7,794
Public Service Company of New Mexico | Other Postretirement Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	10	23	38
Interest cost	1,914	1,907	2,453
Expected return on plan assets	(4,351)	(4,167)	(5,548)
Amortization of net loss	0	0	348
Curtailment loss	836	0	0
Net periodic benefit cost	(1,591)	(2,237)	(2,709)
Public Service Company of New Mexico | Executive Retirement Program
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	0
Interest cost	362	363	491
Amortization of net loss	327	395	403
Amortization of prior service cost	0	0	0
Net periodic benefit cost	689	758	894
Texas-New Mexico Power Company | Pension Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	0
Interest cost	1,720	1,741	2,177
Expected return on plan assets	(2,472)	(3,181)	(3,284)
Amortization of net loss	932	1,247	1,258
Amortization of prior service cost	0	0	0
Settlement loss	1,033	746	0
Net periodic benefit cost	1,213	553	151
Texas-New Mexico Power Company | Other Postretirement Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	38	45	46
Interest cost	307	308	373
Expected return on plan assets	(418)	(407)	(538)
Amortization of net loss	(520)	(322)	(323)
Curtailment loss	0	0
Net periodic benefit cost	(593)	(376)	(442)
Texas-New Mexico Power Company | Executive Retirement Program
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	0
Interest cost	11	17	22
Amortization of net loss	0	33	24
Amortization of prior service cost	0	0	0
Net periodic benefit cost	$ 11	$ 50	$ 46