Lease Commitments - Schedule of Future Expected Lease Payments (Details) $ in Thousands	Mar. 31, 2025 USD ($)
Financing
Remainder of 2025	$ 8,009
2026	8,905
2027	6,111
2028	3,114
2029	1,024
Later years	234
Total minimum lease payments	27,397
Less: Imputed interest	1,937
Lease liabilities	25,460
Energy Storage
Operating
Remainder of 2025	15,250
2026	20,333
2027	20,333
2028	20,333
2029	20,333
Later years	287,100
Total minimum lease payments	383,682
Less: Imputed interest	151,525
Lease liabilities	232,157
Other
Operating
Remainder of 2025	7,657
2026	7,128
2027	7,134
2028	7,135
2029	7,114
Later years	4,012
Total minimum lease payments	40,180
Less: Imputed interest	4,321
Lease liabilities	35,859
PNM
Financing
Remainder of 2025	3,879
2026	4,672
2027	3,372
2028	1,969
2029	672
Later years	230
Total minimum lease payments	14,794
Less: Imputed interest	1,058
Lease liabilities	13,736
PNM \| Energy Storage
Operating
Remainder of 2025	15,250
2026	20,333
2027	20,333
2028	20,333
2029	20,333
Later years	287,100
Total minimum lease payments	383,682
Less: Imputed interest	151,525
Lease liabilities	232,157
PNM \| Other
Operating
Remainder of 2025	7,060
2026	7,045
2027	7,049
2028	7,052
2029	7,039
Later years	3,660
Total minimum lease payments	38,905
Less: Imputed interest	4,141
Lease liabilities	34,764
TNMP
Financing
Remainder of 2025	3,854
2026	3,867
2027	2,395
2028	982
2029	318
Later years	4
Total minimum lease payments	11,420
Less: Imputed interest	790
Lease liabilities	10,630
Operating
Remainder of 2025	547
2026	14
2027	14
2028	11
2029	0
Later years	0
Total minimum lease payments	586
Less: Imputed interest	25
Lease liabilities	$ 561

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.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-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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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next 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 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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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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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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 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 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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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-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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