Pension and Other Postretirement Benefits Pension Benefit Payments are Expected to be Paid (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Public Service Company of New Mexico [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	$ 53,472
2016	53,468
2017	51,241
2018	49,640
2019	48,560
Years 2019 - 2023	213,759
Public Service Company of New Mexico [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	6,560
2016	6,635
2017	6,718
2018	6,875
2019	6,950
Years 2019 - 2023	34,585
Public Service Company of New Mexico [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	1,528
2016	1,510
2017	1,490
2018	1,468
2019	1,445
Years 2019 - 2023	6,722
Texas-New Mexico Power Company [Member] \| Pension Plan [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	5,997
2016	5,667
2017	5,351
2018	5,585
2019	5,188
Years 2019 - 2023	23,600
Texas-New Mexico Power Company [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	801
2016	822
2017	838
2018	860
2019	882
Years 2019 - 2023	4,717
Texas-New Mexico Power Company [Member] \| Executive Retirement Program [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2015	93
2016	92
2017	91
2018	89
2019	86
Years 2019 - 2023	$ 384

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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=35743120&loc=d3e1928-114920

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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

+ Details

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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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