Financing - Long-term Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Long-term Debt, by Maturity [Abstract]
2024	$ 280,529
2025	860,907
2026	667,648
2027	67,721
2028	301,162
Thereafter	2,347,776
Total	4,525,743	$ 4,077,543
PNMR
Long-term Debt, by Maturity [Abstract]
2024	0
2025	500,000
2026	500,000
2027	0
2028	0
Thereafter	0
Total	1,000,000	1,000,000
PNM
Long-term Debt, by Maturity [Abstract]
2024	200,529
2025	360,907
2026	107,648
2027	7,721
2028	241,162
Thereafter	1,354,578
Total	2,272,545	2,009,345
TNMP
Long-term Debt, by Maturity [Abstract]
2024	80,000
2025	0
2026	60,000
2027	60,000
2028	60,000
Thereafter	993,198
Total	$ 1,253,198	$ 1,068,198

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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