Pension and Other Postretirement Benefits Pension Benefit Payments are Expected to be Paid (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Public Service Company of New Mexico [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	$ 1,535
2015	1,516
2016	1,494
2017	1,468
2018	1,438
Years 2019 - 2023	6,580
Public Service Company of New Mexico [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	6,586
2015	6,720
2016	6,943
2017	7,080
2018	7,306
Years 2019 - 2023	36,569
Public Service Company of New Mexico [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	54,356
2015	52,532
2016	52,204
2017	50,954
2018	49,325
Years 2019 - 2023	222,241
Texas-New Mexico Power Company [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	93
2015	92
2016	90
2017	88
2018	85
Years 2019 - 2023	365
Texas-New Mexico Power Company [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	787
2015	795
2016	815
2017	833
2018	852
Years 2019 - 2023	4,558
Texas-New Mexico Power Company [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2014	6,111
2015	6,181
2016	5,831
2017	5,631
2018	5,696
Years 2019 - 2023	$ 23,804

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ 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=28361610&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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