Pension and Other Postretirement Benefits - Pension Benefit Payments are Expected to be Paid (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Public Service Company of New Mexico \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	$ 45,957
2023	44,632
2024	43,427
2025	42,158
2026	40,424
2027 - 2031	183,548
Public Service Company of New Mexico \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	5,924
2023	5,772
2024	5,577
2025	5,229
2026	5,006
2027 - 2031	20,815
Public Service Company of New Mexico \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	1,267
2023	1,228
2024	1,183
2025	1,133
2026	1,077
2027 - 2031	4,455
Texas-New Mexico Power Company \| Pension Plan
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	4,928
2023	4,689
2024	4,459
2025	4,386
2026	4,260
2027 - 2031	18,130
Texas-New Mexico Power Company \| Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	613
2023	638
2024	657
2025	661
2026	669
2027 - 2031	3,113
Texas-New Mexico Power Company \| Executive Retirement Program
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2022	68
2023	62
2024	56
2025	50
2026	44
2027 - 2031	$ 135

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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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 second fiscal year following current fiscal year.

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