Financing Schedule of Long-term Debt Maturities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Long-term Debt, by Maturity [Abstract]
2015	$ 333,066
2016	100,000
2017	57,000
2018	450,025
2019	172,302
Thereafter	842,743
Total	1,955,136us-gaap_DebtInstrumentCarryingAmount
PNMR [Member]
Long-term Debt, by Maturity [Abstract]
2015	118,766
2016	0
2017	0
2018	0
2019	0
Thereafter	0
Total	118,766
Public Service Company of New Mexico [Member]
Long-term Debt, by Maturity [Abstract]
2015	214,300
2016	100,000
2017	57,000
2018	450,025
2019	0
Thereafter	669,545
Total	1,490,870
Texas-New Mexico Power Company [Member]
Long-term Debt, by Maturity [Abstract]
2015	0
2016	0
2017	0
2018	0
2019	172,302
Thereafter	173,198
Total	$ 345,500

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing 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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing 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.

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