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Stock-Based Compensation - Excess Tax Benefits (Details) - Accounting Standards Update 2016-09 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Public Service Company of New Mexico
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from share-based compensation, operating activities	$ 279	$ 559	$ 1,007
Texas-New Mexico Power Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from share-based compensation, operating activities	112	236	377
PNMR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from share-based compensation, operating activities	$ 391	$ 795	$ 1,384

X

- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=120383193&loc=d3e11374-113907

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+ References

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