Income Taxes - Carryforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Taxes, Impairment of Carryforwards
Federal tax credit carryforwards	$ 187	$ 1,029	$ (425)
Compensation expense	199	119	96
Income Taxes, Reserve Balances
Federal tax credit carryforwards	1,216	1,029
Compensation expense	725	526
Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforwards	382,000
Federal tax credit carryforwards that expire beginning in 2023	123,800
Public Service Company of New Mexico
Income Taxes, Impairment of Carryforwards
Federal tax credit carryforwards	427	0	0
Compensation expense	140	84	61
Income Taxes, Reserve Balances
Federal tax credit carryforwards	427	0
Compensation expense	483	343
Texas-New Mexico Power Company
Income Taxes, Impairment of Carryforwards
Federal tax credit carryforwards	0	0	0
Compensation expense	59	35	$ 35
Income Taxes, Reserve Balances
Federal tax credit carryforwards	0	0
Compensation expense	$ 241	$ 182