XML 93 R62.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Lease Commitments - Schedule of Rent Expense (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
PNMR |  |  |
Operating lease expense [Line Items] |  |  |
Operating lease expense | $ 35,972 | $ 37,432 | $ 61,088
Public Service Company of New Mexico |  |  |
Operating lease expense [Line Items] |  |  |
Operating lease expense | 31,817 | 32,843 | 55,994
Texas-New Mexico Power Company |  |  |
Operating lease expense [Line Items] |  |  |
Operating lease expense | $ 3,570 | $ 3,748 | $ 3,688

X
- Definition Operating lease expense [Line Items] + References No definition available. + Details
Name: | pnm_OperatingLeaseExpenseLineItems
Namespace Prefix: | pnm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
Name: | us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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