Schedule I - Condensed Financial Information of Parent Company - Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 4,078	$ 1,104
Income taxes receivable	2,351	4,878
Other current assets	31,624	1,635
Total current assets	410,978	324,600
Property, plant and equipment, net of accumulated depreciation of $17,721 and $16,585	6,972,823	6,752,899
Other long-term assets	177	265
Total assets	9,257,377	8,666,885	$ 7,939,854
Liabilities and Stockholders’ Equity
Short-term debt	232,000	62,700
Accrued interest and taxes	76,783	70,105
Dividends Payable, Current	31,676	132
Other current liabilities	87,037	99,149
Total current liabilities	890,370	664,213
Long-term debt, net of Unamortized Premiums, Discounts, and Debt Issuance Costs	3,892,594	3,519,580
Total liabilities	7,000,922	6,432,427
Common stock (no par value; 120,000,000 shares authorized; issued and outstanding 85,834,874 shares)	1,429,102	1,429,257
Accumulated other comprehensive income (loss), net of income taxes	(66,048)	(71,936)
Retained earnings	828,878	810,203
Total PNMR common stockholders’ equity	2,191,932	2,167,524
Total liabilities and stockholders' equity	9,257,377	8,666,885
PNM Resources
Assets
Cash and cash equivalents	61	63
Intercompany receivables	55,304	45,954
Derivative instruments	11,108	0
Income taxes receivable	1,298	18,674
Other current assets	83	247
Total current assets	67,854	64,938
Property, plant and equipment, net of accumulated depreciation of $17,721 and $16,585	21,513	22,649
Investment in subsidiaries	3,118,442	3,006,281
Other long-term assets	45,501	49,220
Total long-term assets	3,185,456	3,078,150
Total assets	3,253,310	3,143,088
Liabilities and Stockholders’ Equity
Short-term debt	9,400	54,900
Short-term debt-affiliate	14,519	15,219
Accrued interest and taxes	3,302	2,564
Dividends Payable, Current	31,544	0
Other current liabilities	197	318
Total current liabilities	58,962	73,001
Long-term debt, net of Unamortized Premiums, Discounts, and Debt Issuance Costs	999,612	899,759
Other long-term liabilities	2,804	2,804
Total liabilities	1,061,378	975,564
Common stock (no par value; 120,000,000 shares authorized; issued and outstanding 85,834,874 shares)	1,429,102	1,429,257
Accumulated other comprehensive income (loss), net of income taxes	(66,048)	(71,936)
Retained earnings	828,878	810,203
Total PNMR common stockholders’ equity	2,191,932	2,167,524
Total liabilities and stockholders' equity	$ 3,253,310	$ 3,143,088