Pension and Other Postretirement Benefits - Pension Benefit Payments are Expected to be Paid (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Public Service Company of New Mexico [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	$ 50,244
2018	48,398
2019	47,696
2020	46,879
2021	45,348
2022 – 2026	209,331
Public Service Company of New Mexico [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	8,425
2018	8,327
2019	8,092
2020	7,965
2021	7,792
2022 – 2026	33,891
Public Service Company of New Mexico [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	1,510
2018	1,487
2019	1,459
2020	1,427
2021	1,391
2022 – 2026	6,228
Texas-New Mexico Power Company [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	5,526
2018	5,728
2019	5,086
2020	5,042
2021	5,294
2022 – 2026	22,509
Texas-New Mexico Power Company [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	803
2018	818
2019	827
2020	839
2021	859
2022 – 2026	4,466
Texas-New Mexico Power Company [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2017	93
2018	92
2019	89
2020	86
2021	83
2022 – 2026	$ 341

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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+ References

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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+ References

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