v3.26.1

Cover Page shares in Thousands, $ in Millions	12 Months Ended
Cover Page shares in Thousands, $ in Millions	Dec. 31, 2025 USD ($) shares
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Entity Public Float \| $	$ 0
Entity Common Stock, Shares Outstanding \| shares	0
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Auditor Firm ID	185
Auditor Name	KPMG, LLP
Auditor Location	Albuquerque, New Mexico
Entity Registrant Name	PNM Energy Transition Bond Company I, LLC
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	414 Silver Ave. SW
Entity Address, City or Town	Albuquerque
Entity Address, State or Province	NM
Entity Address, Postal Zip Code	87102
City Area Code	505
Local Phone Number	241-2700
Entity File Number	333-274433-01
Entity Tax Identification Number	95-3095291
Title of 12(b) Security	None
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction Flag	false
Entity Shell Company	false
Documents Incorporated by Reference	None.
Entity Central Index Key	0001992267
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor [Line Items]
Auditor Name	KPMG, LLP
Auditor Firm ID	185
Auditor Location	Albuquerque, New Mexico
Public Service Company of New Mexico [Member]
Document Information [Line Items]
Entity Registrant Name	Public Service Company of New Mexico
Entity Address, Address Line One	414 Silver Ave. SW
Entity Address, City or Town	Albuquerque
Entity Address, State or Province	NM
Entity Address, Postal Zip Code	87102
City Area Code	505
Local Phone Number	241-2700
Entity File Number	001-06986
Entity Tax Identification Number	85-0019030

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PNM Energy Transition Bond Co I, LLC 10-K