Plan Description - Narrative (Details) - EBP 005 $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($)
EBP, Description of Plan [Line Items]
Automatic annual increase deferral rate, percentage	1.00%
Available eligible earnings, percentage	75.00%
Maximum company matching contribution, percentage	4.50%
Contribution of eligible employees	6.00%
Percentage of distribution upon participant's termination	$ 1
Participant account, minimum borrowing amount	1
Maximum aggregate equal amount	$ 50
Maximum aggregate equal percentage	50.00%
Note receivable from participant, amortization period	5 years
Minimum
EBP, Description of Plan [Line Items]
Contribution of eligible employees compensation	1.00%
Employer contribution withholding percentage	3.00%
Retirement contribution, percentage	13.50%
Outstanding loans interest rates	5.75%
Maximum
EBP, Description of Plan [Line Items]
Contribution of eligible employees compensation	100.00%
Employer contribution withholding percentage	100.00%
Retirement contribution, percentage	20.50%
Outstanding loans interest rates	11.00%

EBP, Employer Contribution, Maximum Compensation Matched, Percentage

No definition available.

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- Definition

EBP, Involuntary Cash-out Limit

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	pnm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Maximum Contribution To Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	pnm_
Data Type:	dtr-types:percentItemType
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- Definition

EBP, Participant Contribution, Retirement Contribution, Maximum Annual Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	pnm_
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- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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