Pension and Other Postretirement Benefits - Schedule of Benefit Payments are Expected to be Paid (Details) $ in Thousands	Dec. 31, 2024 USD ($)
PNM \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	$ 40,927
2026	39,585
2027	38,706
2028	37,373
2029	36,231
2030 - 2034	160,876
PNM \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	4,771
2026	4,560
2027	4,333
2028	4,128
2029	3,871
2030 - 2034	16,604
PNM \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	1,205
2026	1,150
2027	1,089
2028	1,022
2029	952
2030 - 2034	3,699
TNMP \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	4,239
2026	4,188
2027	4,000
2028	3,902
2029	3,759
2030 - 2034	15,464
TNMP \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	589
2026	597
2027	588
2028	585
2029	574
2030 - 2034	2,606
TNMP \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	0
2026	0
2027	0
2028	0
2029	0
2030 - 2034	$ 0

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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