Lease Commitments - Schedule of Future Expected Lease Payments (Details) $ in Thousands	Sep. 30, 2025 USD ($)
Financing
Remainder of 2025	$ 3,520
2026	12,381
2027	9,387
2028	6,242
2029	3,360
Later years	1,518
Total minimum lease payments	36,408
Less: Imputed interest	2,942
Lease liabilities	33,466
Energy Storage
Operating
Remainder of 2025	6,313
2026	25,250
2027	25,250
2028	25,250
2029	25,250
Later years	364,133
Total minimum lease payments	471,446
Less: Imputed interest	184,974
Lease liabilities	286,472
Other
Operating
Remainder of 2025	242
2026	7,130
2027	7,134
2028	7,135
2029	7,114
Later years	4,012
Total minimum lease payments	32,767
Less: Imputed interest	3,708
Lease liabilities	29,059
PNM
Financing
Remainder of 2025	1,533
2026	5,651
2027	4,318
2028	2,872
2029	1,376
Later years	978
Total minimum lease payments	16,728
Less: Imputed interest	1,302
Lease liabilities	15,426
PNM \| Energy Storage
Operating
Remainder of 2025	6,313
2026	25,250
2027	25,250
2028	25,250
2029	25,250
Later years	364,133
Total minimum lease payments	471,446
Less: Imputed interest	184,974
Lease liabilities	286,472
PNM \| Other
Operating
Remainder of 2025	71
2026	7,045
2027	7,049
2028	7,052
2029	7,039
Later years	3,660
Total minimum lease payments	31,916
Less: Imputed interest	3,562
Lease liabilities	28,354
TNMP
Financing
Remainder of 2025	1,886
2026	6,337
2027	4,709
2028	3,193
2029	1,945
Later years	539
Total minimum lease payments	18,609
Less: Imputed interest	1,569
Lease liabilities	17,040
Operating
Remainder of 2025	154
2026	16
2027	14
2028	11
2029	0
Later years	0
Total minimum lease payments	195
Less: Imputed interest	6
Lease liabilities	$ 189

Finance Lease, Liability, to be Paid, after Year Four

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Lessee, Operating Lease, Liability, to be Paid, after Year Four

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-6

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-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Section S99
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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-6

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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