Estimated Installation Capital Costs

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- Definition

Estimated Portion of Total Capital Costs if Requirement Occurred

+ References

No definition available.

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- Definition

Estimated Total Capital Cost If Requirement Occurred

+ References

No definition available.

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- Definition

Public Utilities, Additional Ownership To Be Obtained, in Megawatts

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No definition available.

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- Definition

Public Utilities, Commitments And Contingencies [Line Items]

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- Definition

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

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- Definition

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

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- Definition

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

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No definition available.

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- Definition

Public Utilities, Number of States To Address Regional Haze

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- Definition

Public Utilities, Number of Megawatts Nuclear Generation

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- Definition

Public Utilities, Overall Reduction Of Ownership, in Megawatts

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No definition available.

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- Definition

Public Utilities, Ownership To Be Exchanged, in Megawatts

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- Definition

Public Utilities, Potential to emit tons per year of visibility impairing pollution, maximum

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- Definition

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

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- Definition

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.

+ References

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			9 Months Ended
	Oct. 01, 2014 USD ($) $ / kw MW	Dec. 20, 2013 USD ($) $ / kw MW	Sep. 30, 2015 T / yr state $ / kw MW	Aug. 13, 2015 MW	May. 19, 2015 MW	Jul. 31, 2014 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 (in states) \| state			50
Public utilities, potential to emit tons per year of visibility impairing pollution, maximum (in tons per year) \| 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)		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 occurred \| $								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 occurred \| $								$ 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	20 years
Public utilities, newly identified replacement gas-fired generation, December 2013 (in megawatts)		177
Public utilities, newly identified replacement solar generation, December 2013 (in megawatts)		40
Public utilities, newly identified replacement gas-fired generation (in megawatts)			187
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 (in dollars per kilowatt) \| $ / kw	1,650		1,118
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 (in megawatts)			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 (in megawatts)	134	134		134
Public utilities, proposed value per kilowatt effective January 1, 2018 (in dollars per kilowatt) \| $ / 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)	132	78	132	65	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)		78