Pension and Other Postretirement Benefits - Pension Benefit Payments are Expected to be Paid (Details) $ in Thousands	Dec. 31, 2023 USD ($)
PNM \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	$ 41,797
2025	40,901
2026	39,447
2027	38,563
2028	37,245
2029 - 2033	167,079
PNM \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	5,305
2025	4,948
2026	4,710
2027	4,438
2028	4,213
2029 - 2033	17,817
PNM \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	1,243
2025	1,193
2026	1,136
2027	1,073
2028	1,006
2029 - 2033	3,987
TNMP \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	4,219
2025	4,183
2026	4,169
2027	3,982
2028	3,897
2029 - 2033	16,789
TNMP \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	611
2025	612
2026	620
2027	609
2028	603
2029 - 2033	2,745
TNMP \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	66
2025	58
2026	51
2027	44
2028	37
2029 - 2033	$ 104

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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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