Lease Commitments - Schedule of Future Expected Lease Payments (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Financing
Remainder of 2024	$ 7,271
2025	7,926
2026	6,181
2027	3,526
2028	1,241
Later years	707
Total minimum lease payments	26,852
Less: Imputed interest	2,080
Lease liabilities	24,772
Battery Storage
Battery Storage
Remainder of 2024	7,825
2025	7,867
2026	7,121
2027	7,049
2028	7,049
Later years	10,587
Total minimum lease payments	47,498
Less: Imputed interest	5,536
Lease liabilities	41,962
Other
Battery Storage
Remainder of 2024	8,840
2025	11,786
2026	11,786
2027	11,786
2028	11,786
Later years	172,254
Total minimum lease payments	228,238
Less: Imputed interest	92,547
Lease liabilities	135,691
PNM
Financing
Remainder of 2024	3,333
2025	3,636
2026	3,117
2027	1,885
2028	856
Later years	614
Total minimum lease payments	13,441
Less: Imputed interest	1,136
Lease liabilities	12,305
PNM \| Battery Storage
Battery Storage
Remainder of 2024	7,117
2025	7,082
2026	7,031
2027	7,035
2028	7,038
Later years	10,587
Total minimum lease payments	45,890
Less: Imputed interest	5,457
Lease liabilities	40,433
PNM \| Other
Battery Storage
Remainder of 2024	8,840
2025	11,786
2026	11,786
2027	11,786
2028	11,786
Later years	172,254
Total minimum lease payments	228,238
Less: Imputed interest	92,547
Lease liabilities	135,691
TNMP
Financing
Remainder of 2024	3,909
2025	4,262
2026	3,038
2027	1,615
2028	383
Later years	93
Total minimum lease payments	13,300
Less: Imputed interest	936
Lease liabilities	12,364
Battery Storage
Remainder of 2024	708
2025	785
2026	90
2027	14
2028	11
Later years	0
Total minimum lease payments	1,608
Less: Imputed interest	78
Lease liabilities	$ 1,530

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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- Definition

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).

+ References

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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).

+ References

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- Definition

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.

+ References

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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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Namespace Prefix:	us-gaap_
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- Definition

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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