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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Related Party Transactions (Details) - Related Party - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Services billings: \| TXNM to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	$ 31,547	$ 30,866	$ 97,275	$ 98,270
Services billings: \| TXNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	13,597	12,136	41,833	39,621
Services billings: \| PNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	70	82	204	247
Services billings: \| TNMP to TXNM
Related Party Transaction [Line Items]
Amount of related party transaction	27	22	69	78
Services billings: \| TNMP to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	0	0	0	0
Interest billings: \| TXNM to PNM
Related Party Transaction [Line Items]
Amount of related party transaction	119	49	182	133
Interest billings: \| TXNM to TNMP
Related Party Transaction [Line Items]
Amount of related party transaction	15	24	38	210
Interest billings: \| PNM to TXNM
Related Party Transaction [Line Items]
Amount of related party transaction	$ 110	$ 133	$ 335	$ 398