Financing Schedule of Long-term Debt Maturities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Long-term Debt, by Maturity [Abstract]
2013	$ 2,530
2014	50,000
2015	181,892
2016	0
2017	57,000
Therafter	1,385,070
Total	1,676,492
PNMR [Member]
Long-term Debt, by Maturity [Abstract]
2013	2,530
2014	0
2015	142,592
2016	0
2017	0
Therafter	0
Total	145,122
Public Service Company of New Mexico [Member]
Long-term Debt, by Maturity [Abstract]
2013	0
2014	0
2015	39,300
2016	0
2017	57,000
Therafter	1,119,570
Total	1,215,870
Texas-New Mexico Power Company [Member]
Long-term Debt, by Maturity [Abstract]
2013	0
2014	50,000
2015	0
2016	0
2017	0
Therafter	265,500
Total	$ 315,500

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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