Pension and Other Postretirement Benefits Pension Benefit Payments are Expected to be Paid (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Public Service Company of New Mexico [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	$ 49,963
2017	49,681
2018	48,209
2019	47,476
2020	46,474
2021 – 2025	213,810
Public Service Company of New Mexico [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	6,568
2017	6,667
2018	6,815
2019	6,830
2020	6,875
2021 – 2025	33,268
Public Service Company of New Mexico [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	1,517
2017	1,499
2018	1,477
2019	1,453
2020	1,426
2021 – 2025	6,587
Texas-New Mexico Power Company [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	5,800
2017	5,416
2018	5,697
2019	5,218
2020	4,955
2021 – 2025	23,401
Texas-New Mexico Power Company [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	838
2017	858
2018	880
2019	903
2020	927
2021 – 2025	4,939
Texas-New Mexico Power Company [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2016	93
2017	92
2018	90
2019	88
2020	85
2021 – 2025	$ 371

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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=58740216&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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Amount of benefits from a defined benefit plan expected to be paid in the fourth 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 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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Amount of benefits from a defined benefit plan expected to be paid in the second 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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