Commitments and Contingencies (Details) (USD $)						0 Months Ended			12 Months Ended																12 Months Ended																			12 Months Ended				4 Months Ended	5 Months Ended	12 Months Ended		12 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 21, 2011 mw	Dec. 21, 2011 San Juan Generating Station [Member]	Nov. 08, 2010 Four Corners [Member]	Jun. 18, 2010 Public Service Company of New Mexico [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member]	Dec. 31, 2012 Public Service Company of New Mexico [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Palo Verde Nuclear Generating Station [Member]		Dec. 31, 2012 Public Service Company of New Mexico [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2011 Public Service Company of New Mexico [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Palo Verde Nuclear Generating Station [Member] Nuclear Spent Fuel And Waste Disposal [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] San Juan Generating Station Units 2 and 3 [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Four Corners Units 4 and 5 (Coal) [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] San Juan Generating Station Units 1 and 4 [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Other Deferred Credits [Member] Palo Verde Nuclear Generating Station [Member] Nuclear Spent Fuel And Waste Disposal [Member]	Dec. 31, 2012 Public Service Company of New Mexico [Member] Other Deferred Credits [Member] Palo Verde Nuclear Generating Station [Member] Nuclear Spent Fuel And Waste Disposal [Member]	Jan. 31, 2010 Public Service Company of New Mexico [Member] Minimum [Member] San Juan Generating Station And Four Corners [Member] opp	Jan. 31, 2010 Public Service Company of New Mexico [Member] Maximum [Member] San Juan Generating Station And Four Corners [Member] opp	Dec. 31, 2013 Public Service Company of New Mexico [Member] Coal Supply [Member] San Juan Generating Station [Member]	Dec. 31, 2012 Public Service Company of New Mexico [Member] Coal Supply [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Surface [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Surface [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2012 Public Service Company of New Mexico [Member] Surface [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Surface [Member] San Juan Generating Station [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Underground [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2012 Public Service Company of New Mexico [Member] Underground [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Underground [Member] San Juan Generating Station [Member] Loss on Long-term Purchase Commitment [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Nuclear Plant [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Nuclear Plant [Member] Maximum [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Commercial Providers [Member] Nuclear Plant [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2013 Public Service Company of New Mexico [Member] Industry Wide Retrospective Assessment Program [Member] Nuclear Plant [Member] Palo Verde Nuclear Generating Station [Member]	Dec. 31, 2013 Pnm Electric [Member] San Juan Generating Station Units 2 and 3 [Member]	Dec. 31, 2013 PNMR and PNM [Member] Palo Verde Nuclear Generating Station Unit 3 [Member] MW	Dec. 31, 2013 Fuel and purchased power adjustment clause [Member] Public Service Company of New Mexico [Member] Minimum [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Fuel and purchased power adjustment clause [Member] Public Service Company of New Mexico [Member] Maximum [Member] San Juan Generating Station [Member]	Apr. 12, 2012 Sierra Club Allegations [Member] San Juan Generating Station [Member]	Apr. 12, 2012 Sierra Club Allegations [Member] Public Service Company of New Mexico [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Clean Air Act related to Regional Haze [Member] state	Dec. 31, 2013 Clean Air Act related to Post-Combustion Controls [Member] Public Service Company of New Mexico [Member] Four Corners [Member] compliance_alternative	Dec. 31, 2013 Clean Air Act related to Post-Combustion Controls [Member] Public Service Company of New Mexico [Member] Four Corners Units 4 and 5 (Coal) [Member]	Dec. 31, 2013 Mercury Control [Member] Public Service Company of New Mexico [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Mercury Control [Member] Public Service Company of New Mexico [Member] Maximum [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] San Juan Generating Station Unit 4 [Member] MW	Dec. 31, 2013 Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] San Juan Generating Station [Member] MW	Apr. 30, 2014 Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] San Juan Generating Station Units 2 and 3 [Member]	Sep. 30, 2014 Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] San Juan Generating Station Units 2 and 3 [Member]	Dec. 31, 2013 Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] San Juan Generating Station Units 2 and 3 [Member] MW	Dec. 31, 2013 Clean Air Act, SNCR [Member] PNMR and PNM [Member] Palo Verde Nuclear Generating Station Unit 3 [Member] MW	Dec. 31, 2013 Loss on Long-term Purchase Commitment [Member] Public Service Company of New Mexico [Member]	Dec. 31, 2012 Loss on Long-term Purchase Commitment [Member] Public Service Company of New Mexico [Member]	Dec. 31, 2013 Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] Minimum [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] Maximum [Member] San Juan Generating Station [Member]	Dec. 31, 2013 Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] Clean Air Act, SNCR [Member] Public Service Company of New Mexico [Member] Maximum [Member] San Juan Generating Station Units 1 and 4 [Member]	Dec. 31, 2013 Environmental Protection Agency [Member] Clean Air Act related to Post-Combustion Controls [Member] Public Service Company of New Mexico [Member] Four Corners [Member]	Dec. 31, 2013 Environmental Protection Agency [Member] WildEarth Guardians filed an action to challenge EPA's rule in the Tenth Circuit [Member] San Juan Generating Station [Member]	Dec. 31, 2013 San Juan Underground Mine Fire [Member] Fuel and purchased power adjustment clause [Member] Public Service Company of New Mexico [Member] San Juan Generating Station [Member]	Dec. 31, 2013 NMTRD Coal Severance Tax [Member] Four Corners [Member]	Dec. 31, 2013 NMTRD Coal Severance Tax [Member] Public Service Company of New Mexico [Member] Four Corners [Member]	Jan. 06, 2014 Navajo Nation Allottee Matters [Member] Public Service Company of New Mexico [Member]	Dec. 31, 2013 San Juan Generating Station [Member] Continuous Highwall Mining [Member]	Dec. 31, 2013 San Juan Generating Station [Member] SJCC Arbitration [Member]	Dec. 31, 2013 San Juan Generating Station [Member] SJCC Arbitration [Member] Public Service Company of New Mexico [Member]
Loss Contingencies [Line Items]
Payments to Acquire Investments to be Held in Decommissioning Trust Fund									$ 4,900,000		$ 2,600,000	$ 2,600,000
Decommissioning Fund Investments, Fair Value									222,500,000		189,000,000
Litigation Settlement, Gross						1,300,000
Loss Contingency, Estimate of Possible Loss													58,000,000														55,700,000			93,300,000												80,300,000
Mine Reclamation and Closing Liability, Noncurrent																		11,900,000	13,900,000						23,800,000	26,800,000		7,800,000	4,200,000
Public Utilities, Number of States To Address Regional Haze																																									50
Public Utilities, Potential to emit tons per year of visibility impairing pollution, maximum																																									250
Public Utilities, Proposed Seeking Shorter Compliance Period																																																										5 years
Public Utilities, Number of years after issuance of final determination to achieve compliance with requirements																																																									3 years
Estimated Total Capital Cost If Requirement Occured																																																						824,000,000	910,000,000
Estimated Installation Capital Costs																																																						85,000,000	90,000,000	82,000,000
Estimated Portion of Total Capital Costs if Requirement Occured																																																						105,000,000	110,000,000
Jointly Owned Utility Plant, Proportionate Ownership Share									10.20%	[1]				46.30%		13.00%	52.00%
Net book value															287,000,000
Public Utilities, Time Period from completed application to EPA Proposed Action																																																135 days
Public Utilities, Time Period from EPA Proposed Action to Final Action																																																	150 days
Public Utilities, Requested Time Period to Recover Retired Units NBV																																																		20 years
Public Utilities, Expected NBV of Units at Retirement																																																		205,000,000
Public Utilities, Number of Megawatts Nuclear Generation																																				134															134
Public Utilities, Proposed value per Kilowatt effective January 1, 2018																																																			2,500
Public Utilities, Additional Ownership To Be Obtained, in Megawatts																																														78
Public Utilities, Overall Reduction Of Ownership, in Megawatts																																															340
Public Utilities, Number of Mega Watts of Gas-fired Generation																																																		177
Public Utilities, Newly Identified Replacement Solar Generation, in Megawatts, December2013																																																		40
estimated cost of replacing gas fired peaking capacity due to retirement of SJGS units																																			276,300,000
Public Utilities, Number of Compliance alternatives																																										2
Public Utilities, Ownership Percentage																																											13.00%
Public Utilities, Government Standard Emission Limit (pounds per MMBTU, parts per million)																				0.060	0.070																					0.015
Public Utilitites, Plant Requirment to Meet Opacity Limit, Percentage																																										20.00%
Public Utilities, Rule Imposes Opacity Limitation on Certain Fugitive Dust Emissions From Coal and Material Handling Operations																																										20.00%
Public Utilities, Jointly Owned Utility Plant, Sale of Ownership Percentage					48.00%
Current Annual Mercury Control Costs																																												700,000
Contingent Estimated Annual Mercury Control Cost																																													6,600,000
Estimated Total Litigation Settlement Cost																																							10,200,000
Estimated Company Share Litigation Settlement Cost																																								4,500,000
Minimum Megawatt Capacity from Coal and Oil-Fired Electric Generating Units under Jurisdiction of the Merucy and Air Toxics Standards			25
Mercury Removal Rate, Percentage				99.00%
Other, net	34,590,000	31,490,000					30,510,000	27,457,000														12,300,000	9,900,000
Public Utilities, Estimated Increase in Coal Cost, Percentage																						26.00%
Public Utilities, Annual Funding																																																				300,000	3,500,000
Public Utilities, Expected Funding Annual Requirements																																																				600,000
Final Reclamation, capped amount to be collected																									100,000,000
Regulatory Assets							403,611,000	468,446,000																100,000,000
Preliminary estimate increased deferral related to mine fire incident																																					17,400,000	21,600,000
Public Utilities, Insurance Recovery																																																											18,700,000
Public Utilities, Proposed Retroactive Surface Mining Royalty Rate																																																															12.50%
Public Utilities, Current Surface Mining Royalty Rate applied between 2000 and 2003																																																															8.00%
Public Utilities, Estimated Underpaid Surface Mining Royalties under proposed rate change																																																															5,000,000
Public Utilities, PNM Share Estimated Underpaid Surface Mining Royalties under proposed rate change																																																															46.30%
Public Utilities, SJCC Disputed Mining Costs																																																																1,500,000.0
Public Utilities, PNM Share of SJCC Disputed Mining Costs																																																																700,000
Public Utilities, PNM Share of SJCC Disputed Mining Costs to pass through FPPAC																																																																500,000
Public Utilities, Potential Unbilled Mining Costs Owed to SJCC																																																																5,200,000.0
Public Utilities, Potential Overbilled Mining Costs SJCC Owes to SJGS Owners																																																																1,100,000.0
Public Utilities, Potential Capital Improvements billed as Mining Costs to SJGS Owners																																																																13,900,000.0
Public Utilities, PNM Share of arbitration ruling																																																																	46.30%
Public Utilities, FFPAC Percentage of mining costs overbilled or unbilled ruled by arbitration																																																																	33.00%
Public Utilities, FFPAC Percentage of capital improvements billed as mining costs ruled by arbitration																																																																	25.00%
Public Utilities, Assessed Coal Severance Surtax Penalty and Interest																																																												30,000,000
Public Utilities, PNM Share Assessed Coal Severance Surtax Penalty and Interest to pass through FFPAC																																																													8.00%
Public Utilities, Liability Insurance Coverage																																13,600,000,000	375,000,000	13,200,000,000
Public Utilities, Ownership Percentage in Nuclear Reactor																															10.20%
Public Utilities, Maximum Potential Assessment Per Incident																															38,900,000
Public Utilities, Annual Payment Limitation Related to Incident																															5,700,000
Public Utilities, Aggregate Amount of All Risk Insurance																															2,750,000,000
Public Utilities, Sublimit Amount under Nuclear Electric Insurance Limited																															1,500,000,000
Public Utilities, Maximum Amount under Nuclear Electic Insurance Limited																															$ 4,300,000
Number of allotment parcels' appraisal requested for review																																																														58

[1] Includes interest in PVNGS Unit 3, interest in common facilities for all PVNGS units, and owned interests in PVNGS Units 1 and 2.