Debt Instrument, Extension Period

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Number Of Extensions

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instruments, NMPRC Approved Credit Facility

+ References

No definition available.

+ Details

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Namespace Prefix:	pnm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of assets pledged to secure a debt instrument.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Financing - Short-term Debt and Liquidity (Details)		1 Months Ended				9 Months Ended
Financing - Short-term Debt and Liquidity (Details)	Apr. 01, 2024 extension_option	Aug. 31, 2026 USD ($)	Jul. 31, 2026 USD ($)	Feb. 28, 2026 USD ($)	Nov. 30, 2025 USD ($)	Sep. 30, 2025 USD ($) extension_option	Dec. 31, 2024 USD ($)	May 20, 2022 USD ($)
Short-term Debt [Line Items]
Letters of credit outstanding						$ 3,100,000
ETBC 1 \| Forecast
Short-term Debt [Line Items]
Scheduled payments		$ 3,700,000		$ 3,600,000
PNM 2024 Note Purchase Agreement \| Forecast
Short-term Debt [Line Items]
Scheduled payments					$ 200,000,000
PNM 2025 Note Purchase Agreement \| Forecast
Short-term Debt [Line Items]
Scheduled payments			$ 195,000,000
Public Service Company of New Mexico
Short-term Debt [Line Items]
Letters of credit outstanding						0
TXNM and PNM
Short-term Debt [Line Items]
Notes payable						1,700,000	$ 1,500,000
Texas-New Mexico Power Company
Short-term Debt [Line Items]
Letters of credit outstanding						0
PNM and TNMP \| Pollution Control Revenue Bonds \| Bonds
Short-term Debt [Line Items]
Long-term debt						0	$ 0
Revolving Credit Facility \| Line of credit
Short-term Debt [Line Items]
Financing capacity						300,000,000.0
Revolving Credit Facility \| Line of credit \| Public Service Company of New Mexico
Short-term Debt [Line Items]
Financing capacity						400,000,000.0
Revolving Credit Facility \| Line of credit \| Public Service Company of New Mexico \| PNM New Mexico Credit Facility
Short-term Debt [Line Items]
NMPRC approved credit facility								$ 40,000,000.0
Revolving Credit Facility \| Line of credit \| TXNM and PNM
Short-term Debt [Line Items]
Number of extensions \| extension_option	2
Extension period	1 year
Revolving Credit Facility \| Line of credit \| Texas-New Mexico Power Company
Short-term Debt [Line Items]
Financing capacity						$ 200,000,000
Number of extensions \| extension_option						2
Extension period						1 year
Revolving Credit Facility \| Line of credit \| Texas-New Mexico Power Company \| First Mortgage Bonds Due 2029
Short-term Debt [Line Items]
Collateral amount						$ 200,000,000
TXNM Revolving Credit Facility \| WEB LOC Facility
Short-term Debt [Line Items]
Letters of credit outstanding						$ 30,300,000