XML 77 R57.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Regulatory and Rate Matters - TNMP Narrative (Details) - Texas-New Mexico Power Company [Member] |  |  |  | 1 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 27, 2016 USD ($) | Jul. 19, 2016 USD ($) | May 27, 2016 USD ($) | Jul. 30, 2011 USD ($) | Sep. 09, 2016 USD ($) | Jun. 30, 2016 USD ($) | Mar. 22, 2016 USD ($) | Sep. 09, 2015 USD ($) | Mar. 15, 2015 USD ($) | Aug. 05, 2016 customer | Oct. 02, 2015 USD ($) | Aug. 15, 2013 USD ($) customer
Advanced Meter System Deployment and Surcharge Request [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved deployment costs |  |  |  | $ 113,400,000 |  |  |  |  |  |  |  |
Collection of deployment costs through surcharge period |  |  |  | 12 years |  |  |  |  |  |  |  |
Completion period of advanced meter deployment |  |  |  | 5 years |  |  |  |  |  |  |  |
Recovery in cost through initial fees |  |  |  |  |  |  |  |  |  |  |  | $ 200,000
Ongoing annual expenses |  |  |  |  |  |  |  |  |  |  |  | 500,000
Approved non-standard metering ongoing expenses monthly charge |  |  |  |  |  |  |  |  |  |  |  | $ 36.78
Presumed number of customers that will elect non-standard meter service (in customers) | customer |  |  |  |  |  |  |  |  |  |  |  | 1,081
Cost and savings reconciliation filed with regulators, capital cost savings |  |  |  |  |  |  |  |  |  |  | $ 71,000,000 |
Cost and savings reconciliation filed with regulators, operations and maintenance savings |  |  |  |  |  |  |  |  |  |  | $ 18,000,000 |
Program costs incurred to date |  |  |  |  |  | $ 1,500,000 |  |  |  |  |  |
Advanced Meter System Deployment and Surcharge Request [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Current number of customers that have elected non-standard meter service (in customers) | customer |  |  |  |  |  |  |  |  |  | 101 |  |
Advanced Meter System Deployment and Surcharge Request [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved non-standard metering service cost, initial fee range |  |  |  |  |  |  |  |  |  |  |  | $ 63.97
Advanced Meter System Deployment and Surcharge Request [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved non-standard metering service cost, initial fee range |  |  |  |  |  |  |  |  |  |  |  | $ 168.61
Transmission Cost of Service Rates [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Annual increase in revenue |  |  |  |  |  |  | $ 1,400,000 | $ 4,400,000 | $ 4,200,000 |  |  |
Transmission Cost of Service Rates [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease) |  | $ 9,500,000 |  |  |  |  |  |  |  |  |  |
Annual increase in revenue |  | $ 1,800,000 |  |  | $ 4,300,000 |  |  |  |  |  |  |
Energy Efficiency [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested adjustment to EECRF |  |  | $ 6,100,000 |  |  |  |  |  |  |  |  |
Requested adjustment to EECRF, performance bonus |  |  | $ 800,000 |  |  |  |  |  |  |  |  |
Energy Efficiency [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved program cost recovery | $ 6,000,000 |  |  |  |  |  |  |  |  |  |  |
Approved performance bonus | $ 800,000 |  |  |  |  |  |  |  |  |  |  |

X
- Definition Current number of customers that have elected non-standard meter service + References No definition available. + Details
Name: | pnm_Currentnumberofcustomersthathaveelectednonstandardmeterservice
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Presumed number of customers that will elect non-standard meter service + References No definition available. + Details
Name: | pnm_Presumednumberofcustomersthatwillelectnonstandardmeterservice
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Public Utilities, Approved Cost Recovery Factor, Performance Bonus + References No definition available. + Details
Name: | pnm_PublicUtilitiesApprovedCostRecoveryFactorPerformanceBonus
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Approved Cost Recovery Factor, Program Costs + References No definition available. + Details
Name: | pnm_PublicUtilitiesApprovedCostRecoveryFactorProgramCosts
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Approved Deployment Costs + References No definition available. + Details
Name: | pnm_PublicUtilitiesApprovedDeploymentCosts
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Public Utilities, Approved Non-standard metering ongoing expenses monthly charge + References No definition available. + Details
Name: | pnm_PublicUtilitiesApprovedNonstandardmeteringongoingexpensesmonthlycharge
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Approved Non-standard metering service cost initial fee range + References No definition available. + Details
Name: | pnm_PublicUtilitiesApprovedNonstandardmeteringservicecostinitialfeerange
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Collection of Deployment Costs Through Surcharge Period + References No definition available. + Details
Name: | pnm_PublicUtilitiesCollectionOfDeploymentCostsThroughSurchargePeriod
Namespace Prefix: | pnm_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public Utilities, Completion Period of Advanced Meter Deployment + References No definition available. + Details
Name: | pnm_PublicUtilitiesCompletionPeriodOfAdvancedMeterDeployment
Namespace Prefix: | pnm_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public Utilities, Cost and savings reconciliation filed with regulators, capital cost savings + References No definition available. + Details
Name: | pnm_PublicUtilitiesCostandsavingsreconciliationfiledwithregulatorscapitalcostsavings
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Cost and savings reconciliation filed with regulators, operations and maintenance savings + References No definition available. + Details
Name: | pnm_PublicUtilitiesCostandsavingsreconciliationfiledwithregulatorsoperationsandmaintenancesavings
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Increase Annual Transmission Service Revenue + References No definition available. + Details
Name: | pnm_PublicUtilitiesIncreaseAnnualTransmissionServiceRevenue
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Non-standard metering ongoing expenses total to be borne by opt-out customers + References No definition available. + Details
Name: | pnm_PublicUtilitiesNonstandardmeteringongoingexpensestotaltobebornebyoptoutcustomers
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Non-standard metering service cost total to be borne by opt-out customers + References No definition available. + Details
Name: | pnm_PublicUtilitiesNonstandardmeteringservicecosttotaltobebornebyoptoutcustomers
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public Utilities, Program costs incurred to date + References No definition available. + Details
Name: | pnm_PublicUtilitiesProgramcostsincurredtodate
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Public Utilities, Proposed Cost Recovery Factor, Performance Bonus + References No definition available. + Details
Name: | pnm_PublicUtilitiesProposedCostRecoveryFactorPerformanceBonus
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Proposed Cost Recovery Factor, Program Costs + References No definition available. + Details
Name: | pnm_PublicUtilitiesProposedCostRecoveryFactorProgramCosts
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesGeneralDisclosuresLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=pnm_TexasNewMexicoPowerCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_AdvancedMeterSystemDeploymentAndSurchargeRequestMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_TransmissionCostOfServiceRatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | pnm_ScheduleOfRegulatoryRateMattersAxis=pnm_EnergyEfficiencyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |