XML 85 R60.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Stockholders' Equity (Details) - USD ($) |  | 1 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Nov. 26, 2018 | Jul. 31, 2018 | Jun. 30, 2018 | Sep. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Class of Stock [Line Items] |  |  |  |  |  |  |
Payment of dividends |  |  |  |  | $ 306,800,000 |  |
Line of Credit |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt-to-capital ratio (not more than) | 3.32% | 70.00% | 65.00% | 65.00% | 70.00% |  |
Public Service Company of New Mexico |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Equity contribution from parent |  |  |  |  | $ 0 | $ 0 | $ 28,142,000
Payment of dividends |  |  |  |  | $ 242,800,000 |  |
Preferred stock, dividend rate |  |  |  |  | 4.58% |  |
Preferred stock, redemption percent |  |  |  |  | 102.00% |  |
Preferred stock outstanding (in shares) |  |  |  |  | 115,293 | 115,293 |
Preferred stock, cumulative shares authorized (in shares) |  |  |  |  | 10,000,000 | 10,000,000 |
Public Service Company of New Mexico | Maximum |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Requirement to obtain approval to transfer more than a percentage of PNM's assets |  |  |  |  | 5.00% |  |
Public Service Company of New Mexico | Line of Credit |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt-to-capital ratio (not more than) |  |  |  |  | 65.00% |  |
Public Service Company of New Mexico | Affiliated Entity |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Cash dividends paid to parent company by consolidated subsidiaries |  |  |  |  | $ 77,400,000 | $ 60,700,000 | 4,100,000
Texas-New Mexico Power Company |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Equity contribution from parent |  |  |  |  | $ 30,000,000 | 50,000,000 | 50,000,000
Preferred stock, cumulative shares authorized (in shares) |  |  |  |  | 1,000,000 |  |
Texas-New Mexico Power Company | Line of Credit |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt-to-capital ratio (not more than) |  |  |  |  | 65.00% |  |
Texas-New Mexico Power Company | Affiliated Entity |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Cash dividends paid to parent company by consolidated subsidiaries |  |  |  |  | $ 41,900,000 | $ 44,400,000 | $ 31,800,000
PNMR and TNMP |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Preferred stock outstanding (in shares) |  |  |  |  | 0 |  |
PNMR and TNMP | Line of Credit |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt-to-capital ratio (not more than) |  | 70.00% |  |  |  |  |

X
- Definition Financial covenants, percentage of assets allowed to transfer + References No definition available. + Details
Name: | pnm_Financialcovenantspercentageofassetsallowedtotransfer
Namespace Prefix: | pnm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Preferred stock, redemption premium percent. + References No definition available. + Details
Name: | pnm_PreferredStockRedemptionPremiumPercent
Namespace Prefix: | pnm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ratio of debt to capital, maximum + References No definition available. + Details
Name: | pnm_RatioOfDebtToCapitalMaximum
Namespace Prefix: | pnm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(b)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 + Details
Name: | us-gaap_Dividends
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PreferredStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PreferredStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from parent as a source of financing that is recorded as additional paid in capital. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromContributionsFromParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
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: | dei_LegalEntityAxis=pnm_PNMRandTNMPMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |