Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss	$ 85,382	$ 32,441
Regulatory liabilities related to income taxes	98,371	120,651
Federal tax credit carryforwards	122,557	122,436
Regulatory disallowances	28,037	38,835
Other	33,849	34,812
Total deferred tax assets	368,196	349,175
Deferred tax liabilities:
Depreciation and plant related	(801,022)	(787,295)
Investment tax credit	96,227	97,409
Regulatory assets related to income taxes	(77,013)	(78,211)
Pension	(40,651)	(40,828)
Regulatory asset for shutdown of SJGS Units 2 and 3	(24,048)	(25,643)
Regulatory asset SJGS investment	(69,828)	0
Other	(82,238)	(84,639)
Total deferred tax liabilities	(1,191,027)	(1,114,025)
Net accumulated deferred income tax liabilities	(822,831)	(764,850)
Public Service Company of New Mexico
Deferred tax assets:
Net operating loss	54,681	1,854
Regulatory liabilities related to income taxes	76,744	96,161
Federal tax credit carryforwards	84,902	86,811
Regulatory disallowances	28,037	38,835
Other	33,079	36,599
Total deferred tax assets	277,443	260,260
Deferred tax liabilities:
Depreciation and plant related	(620,814)	(616,567)
Investment tax credit	74,015	74,187
Regulatory assets related to income taxes	(67,912)	(68,687)
Pension	(36,048)	(36,283)
Regulatory asset for shutdown of SJGS Units 2 and 3	(24,048)	(25,643)
Regulatory asset SJGS investment	(69,828)	0
Other	(66,818)	(69,575)
Total deferred tax liabilities	(959,483)	(890,942)
Net accumulated deferred income tax liabilities	(682,040)	(630,682)
Texas-New Mexico Power Company
Deferred tax assets:
Regulatory liabilities related to income taxes	21,627	24,490
Other	5,353	3,648
Total deferred tax assets	26,980	28,138
Deferred tax liabilities:
Depreciation and plant related	(166,230)	(157,649)
Regulatory assets related to income taxes	(9,213)	(9,525)
Loss on reacquired debt	5,527	5,799
Pension	(4,603)	(4,545)
AMS	3,989	5,249
Other	(2,055)	(2,619)
Total deferred tax liabilities	(191,617)	(185,386)
Net accumulated deferred income tax liabilities	$ (164,637)	$ (157,248)