Schedule I - Condensed Financial Information of Parent Company - Statements of Earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Condensed Financial Statements, Captions [Line Items]
Operating Revenues	$ 1,939,198	$ 2,249,555	$ 1,779,873
Operating Expenses	1,707,858	1,855,795	1,471,720
Operating income	231,340	393,760	308,153
Other Income and Deductions:
Other income	24,204	21,601	20,200
Net other income and (deductions)	49,544	(54,542)	33,153
Interest Charges	190,355	127,908	96,877
Earnings before Income Taxes	90,529	211,310	244,429
Income taxes (benefit)	(16,350)	26,130	32,582
PNM Resources
Condensed Financial Statements, Captions [Line Items]
Operating Revenues	0	0	0
Operating Expenses	4,972	6,199	15,044
Operating income	(4,972)	(6,199)	(15,044)
Other Income and Deductions:
Equity in earnings of subsidiaries	133,628	197,860	221,004
Other income	2,245	663	362
Net other income and (deductions)	135,873	198,523	221,366
Interest Charges	58,934	30,430	11,986
Earnings before Income Taxes	71,967	161,894	194,336
Income taxes (benefit)	(15,851)	(7,636)	(1,493)
Net earnings	$ 87,818	$ 169,530	$ 195,829