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Estimated Installation Capital Costs

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Estimated Portion of Total Capital Costs if Requirement Occurred

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Estimated Total Capital Cost If Requirement Occurred

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Public Utilities, Additional Ownership To Be Obtained, in Megawatts

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Public Utilities, Commitments And Contingencies [Line Items]

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Public Utilities, Newly Identified Replacement Gas-fired Generation, in Megawatts

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Public Utilities, Newly Identified Replacement Gas-fired Generation, in Megawatts, December2013

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Public Utilities, Newly Identified Replacement Solar Generation, in Megawatts, December2013

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Public Utilities, Number of States To Address Regional Haze

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Public Utilities, Number of Megawatts Nuclear Generation

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Public Utilities, Overall Reduction Of Ownership, in Megawatts

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Public Utilities, Ownership To Be Exchanged, in Megawatts

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Public Utilities, Proposed value per Kilowatt effective January 1, 2018

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Public Utilities, Requested Time Period to Recover Retired Units NBV

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 10.C)

-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section C

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Commitments and Contingencies - The Clean Air Act (Details) $ in Millions	Oct. 01, 2014 USD ($) $ / kw MW	Dec. 20, 2013 USD ($) $ / kw MW	Jun. 30, 2015 USD ($) T / yr state MW	May. 19, 2015 MW	Jun. 26, 2014 MW	Oct. 31, 2012 USD ($)
Clean Air Act related to Regional Haze [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Number of States To Address Regional Haze \| state			50
Public Utilities, Potential to emit tons per year of visibility impairing pollution, maximum \| T / yr			250
San Juan Generating Station [Member] \| Public Service Company of New Mexico [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share						46.30%
San Juan Generating Station [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Overall Reduction Of Ownership, in Megawatts \| MW		340
San Juan Generating Station [Member] \| Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] \| Minimum [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SCR [Member] [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated Total Capital Cost If Requirement Occurred						$ 824.0
San Juan Generating Station [Member] \| Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] \| Minimum [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated Installation Capital Costs						85.0
Estimated Portion of Total Capital Costs if Requirement Occured						105.0
San Juan Generating Station [Member] \| Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] \| Maximum [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SCR [Member] [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated Total Capital Cost If Requirement Occurred						910.0
San Juan Generating Station [Member] \| Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] \| Maximum [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated Installation Capital Costs						90.0
Estimated Portion of Total Capital Costs if Requirement Occured						$ 110.0
San Juan Generating Station Units 2 and 3 [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Requested Time Period to Recover Retired Units NBV	20 years	20 years
Public Utilities, Newly Identified Replacement Gas-fired Generation, in Megawatts, December2013 \| MW		177
Public Utilities, Newly Identified Replacement Solar Generation, in Megawatts, December2013 \| MW		40
Public Utilities, Newly Identified Replacement Gas-fired Generation, in Megawatts \| MW			187
San Juan Generating Station Units 2 and 3 [Member] \| Pnm Electric [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated cost of replacing gas fired peaking capacity due to retirement of SJGS units			$ 212.5
Palo Verde Nuclear Generating Station Unit 3 [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Proposed value per Kilowatt effective January 1, 2018 \| $ / kw	1,650
Palo Verde Nuclear Generating Station Unit 3 [Member] \| PNMR and PNM [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Number of Megawatts Nuclear Generation \| MW			134
Palo Verde Nuclear Generating Station Unit 3 [Member] \| PNMR and PNM [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Number of Megawatts Nuclear Generation \| MW	134	134
Public Utilities, Proposed value per Kilowatt effective January 1, 2018 \| $ / kw		2,500
San Juan Generating Station Units 1 and 4 [Member] \| Installation Costs Including Construction Management, Gross Receipts Taxes, AFUDC, and Other PNM Costs [Member] \| Maximum [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Estimated Installation Capital Costs	$ 90.6	$ 82.0
San Juan Generating Station Unit 4 [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Additional Ownership To Be Obtained, in Megawatts \| MW	132	78	132	132	132
San Juan Generating Station Unit 3 [Member] \| Public Service Company of New Mexico [Member] \| Clean Air Act, SNCR [Member]
Public Utilities, Commitments And Contingencies [Line Items]
Public Utilities, Ownership To Be Exchanged, in Megawatts \| MW		78