XML 89 R58.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Financing - Long-term Debt (Details) - USD ($) | Dec. 31, 2016 | Dec. 21, 2016 | Dec. 31, 2015 | Dec. 17, 2015 | Aug. 11, 2015
--- | --- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |  |
Total | $ 2,388,577,000 |  | $ 2,086,370,000 |  |
Principal, Less current maturities | 274,025,000 |  | 125,000,000 |  |
Long-term debt, excluding current maturities, gross | 2,114,552,000 |  | 1,961,370,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | (4,135,000) |  | (5,578,000) |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, Less current maturities | 677,000 |  | 21,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, excluding current maturities | (4,812,000) |  | (5,599,000) |  |
PNMR 2016 Two Year Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt |  | $ 100,000,000.0 |  |  |
Public Service Company of New Mexico [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Total | 1,640,870,000 |  | 1,590,870,000 |  |
Principal, Less current maturities | 232,000,000 |  | 125,000,000 |  |
Long-term debt, excluding current maturities, gross | 1,408,870,000 |  | 1,465,870,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 9,501,000 |  | 10,193,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, Less current maturities | 120,000 |  | 21,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, excluding current maturities | $ 9,381,000 |  | 10,172,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 4.875% due 2033 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 4.875% |  |  |  |
Unsecured long-term debt, noncurrent | $ 0 |  | 146,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 0 |  | 721,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 1.875% due 2033, mandatory tender at October 1, 2021 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 1.875% |  |  |  |
Unsecured long-term debt, noncurrent | $ 146,000,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 1,807,000 |  | 0 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 6.25% due 2038 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 6.25% |  |  |  |
Unsecured long-term debt, noncurrent | $ 36,000,000 |  | 36,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 239,000 |  | 251,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 4.75% due 2040, mandatory tender at June 1, 2017 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 4.75% |  |  |  |
Unsecured long-term debt, noncurrent | $ 37,000,000 |  | 37,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 25,000 |  | 82,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 5.20% due 2040, mandatory tender at June 1, 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 5.20% |  |  |  |
Unsecured long-term debt, noncurrent | $ 40,045,000 |  | 40,045,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 147,000 |  | 190,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 5.90% due 2040 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 5.90% |  |  |  |
Unsecured long-term debt, noncurrent | $ 255,000,000 |  | 255,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 2,131,000 |  | 2,222,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 6.25% due 2040 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 6.25% |  |  |  |
Unsecured long-term debt, noncurrent | $ 11,500,000 |  | 11,500,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 96,000 |  | 100,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 2.54% due 2042, mandatory tender at June 1, 2017 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 2.54% |  |  |  |
Unsecured long-term debt, noncurrent | $ 20,000,000 |  | 20,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 67,000 |  | 199,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 2.40% due 2043, mandatory tender at June 1, 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 2.40% |  |  |  |
Unsecured long-term debt, noncurrent | $ 39,300,000 |  | 39,300,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 340,000 |  | 456,000 |  |
Public Service Company of New Mexico [Member] | Senior Unsecured Notes, Pollution Control Revenue Bonds [Member] | 5.20% due 2043, mandatory tender at June 1, 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 5.20% |  |  |  |
Unsecured long-term debt, noncurrent | $ 21,000,000 |  | 21,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 75,000 |  | 96,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | 7.95% due 2018 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 7.95% |  |  |  |
Unsecured long-term debt, noncurrent | $ 350,000,000 |  | 350,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 995,000 |  | 1,718,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | 7.50% due 2018 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 7.50% |  |  |  |
Unsecured long-term debt, noncurrent | $ 100,025,000 |  | 100,025,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 197,000 |  | 320,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | 5.35% due 2021 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 5.35% |  |  |  |
Unsecured long-term debt, noncurrent | $ 160,000,000 |  | 160,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 780,000 |  | 943,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | 3.85% due 2025 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 3.85% |  |  |  | 3.85%
Unsecured long-term debt, noncurrent | $ 250,000,000 |  | 250,000,000 |  | $ 250,000,000.0
Unamortized Discounts, (Premiums), and Issuance Costs, net | 2,574,000 |  | 2,874,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | PNM Multi-Draw Term Loan Agreement due 2016 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt | 0 |  | 125,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 0 |  | 21,000 |  |
Public Service Company of New Mexico [Member] | Unsecured Debt [Member] | PNM 2016 Term Loan Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt | 175,000,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 28,000 |  | 0 |  |
Texas-New Mexico Power Company [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Total | 405,500,000 |  | 345,500,000 |  |
Principal, Less current maturities | 0 |  | 0 |  |
Long-term debt, excluding current maturities, gross | 405,500,000 |  | 345,500,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | (15,375,000) |  | (15,911,000) |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, Less current maturities | 0 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, excluding current maturities | $ (15,375,000) |  | (15,911,000) |  |
Texas-New Mexico Power Company [Member] | First Mortgage Bonds [Member] | First Mortgage Bonds, 9.50% due 2019, Series 2009A [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 9.50% |  |  |  |
Unsecured long-term debt, noncurrent | $ 172,302,000 |  | 172,302,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 1,857,000 |  | 2,682,000 |  |
Texas-New Mexico Power Company [Member] | First Mortgage Bonds [Member] | First Mortgage Bonds, 6.95% due 2043, Series 2013A [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 6.95% |  |  |  |
Unsecured long-term debt, noncurrent | $ 93,198,000 |  | 93,198,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ (18,773,000) |  | (19,490,000) |  |
Texas-New Mexico Power Company [Member] | First Mortgage Bonds [Member] | First Mortgage Bonds, 4.03% due 2024, Series 2014A [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 4.03% |  |  |  |
Unsecured long-term debt, noncurrent | $ 80,000,000 |  | 80,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 792,000 |  | 897,000 |  |
Texas-New Mexico Power Company [Member] | First Mortgage Bonds [Member] | First Mortgage Bonds, 3.53% due 2026, Series 2016A [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated percentage | 3.53% |  |  | 3.53% |
Unsecured long-term debt, noncurrent | $ 60,000,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 749,000 |  | 0 |  |
PNMR [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Total | 342,207,000 |  | 150,000,000 |  |
Principal, Less current maturities | 42,025,000 |  | 0 |  |
Long-term debt, excluding current maturities, gross | 300,182,000 |  | 150,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 1,739,000 |  | 140,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, Less current maturities | 557,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net, excluding current maturities | 1,182,000 |  | 140,000 |  |
PNMR [Member] | PNMR Term Loan Agreement due 2018 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt | 150,000,000 |  | 150,000,000 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 84,000 |  | 140,000 |  |
PNMR [Member] | BTMU Term Loan Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt | 92,207,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | 1,634,000 |  | 0 |  |
PNMR [Member] | PNMR 2016 Two Year Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt | 100,000,000 |  | 0 |  |
Unamortized Discounts, (Premiums), and Issuance Costs, net | $ 21,000 |  | $ 0 |  |

X
- Definition Long-term debt, Current maturities, Gross + References No definition available. + Details
Name: | pnm_LongtermdebtCurrentmaturitiesGross
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Long-term debt, Excluding current maturities, Gross + References No definition available. + Details
Name: | pnm_LongtermdebtExcludingcurrentmaturitiesGross
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums, Current Portion + References No definition available. + Details
Name: | pnm_UnamortizedLoanCommitmentandOriginationFeesandUnamortizedDiscountsorPremiumsCurrentPortion
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums, Excluding Current Portion + References No definition available. + Details
Name: | pnm_UnamortizedLoanCommitmentandOriginationFeesandUnamortizedDiscountsorPremiumsExcludingCurrentPortion
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533 + Details
Name: | us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_UnsecuredLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_PNMR2016TwoYearTermLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=pnm_SeniorUnsecuredNotesPollutionControlRevenueBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotePcrbDue2033At4Point875PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPcrbDue2033At1Point875PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotePcrbDue2038At6Point25PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotePcrbDue2040At4Point75PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPcrbDue2040At5Point20PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPcrbDue2040At5Point90PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPcrbDue2040At6Point25PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPCRBDue2042at2Point54percentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorunsecurednotePCRBDue2043at2point4percentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesPcrbDue2043At5Point20PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesDue2018At7Point95PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesDue2018At7Point50PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorUnsecuredNotesDue2021At5Point35PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_SeniorunsecurednoteDue2025at3point850percentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_PNMMultiDrawTermLoanAgreementdue2016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_PNM2016TermLoanAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=pnm_FirstMortgageBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_FirstMortgageBondsDue2019Series2009Aat9point50percentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_FirstMortgageBonds6Point95PercentDue2043Series2013AMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_FirstMortgageBondsDue2024Series2014Aat4point03percentMemberMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_FirstMortgageBonds3Point53Percentdue2026Series2016AMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_PNMRTermLoanAgreementdue2018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pnm_BTMUTermLoanAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |