Lease Commitments - Schedule of Future Expected Lease Payments (Details) $ in Thousands	Jun. 30, 2020 USD ($)
Financing
Remainder of 2020	$ 1,842
2021	3,606
2022	3,480
2023	3,241
2024	2,364
Later years	2,811
Total minimum lease payments	17,344
Less: Imputed interest	1,340
Lease liabilities as of June 30, 2020	16,004
Operating
Remainder of 2020	11,686
2021	29,316
2022	28,473
2023	19,423
2024	8,833
Later years	35,489
Total minimum lease payments	133,220
Less: Imputed interest	15,167
Lease liabilities as of June 30, 2020	118,053
PNM
Financing
Remainder of 2020	862
2021	1,688
2022	1,642
2023	1,587
2024	985
Later years	1,019
Total minimum lease payments	7,783
Less: Imputed interest	572
Lease liabilities as of June 30, 2020	7,211
Operating
Remainder of 2020	9,979
2021	26,576
2022	26,266
2023	17,735
2024	7,908
Later years	34,466
Total minimum lease payments	122,930
Less: Imputed interest	13,863
Lease liabilities as of June 30, 2020	109,067
TNMP
Financing
Remainder of 2020	944
2021	1,845
2022	1,766
2023	1,617
2024	1,379
Later years	1,791
Total minimum lease payments	9,342
Less: Imputed interest	761
Lease liabilities as of June 30, 2020	8,581
Operating
Remainder of 2020	1,437
2021	2,448
2022	1,996
2023	1,508
2024	877
Later years	765
Total minimum lease payments	9,031
Less: Imputed interest	705
Lease liabilities as of June 30, 2020	$ 8,326

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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No definition available.

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Balance Type:	na
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating 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 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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- Definition

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

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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