Share-based Compensation Arrangement by Share-based Payment Award, Vesting Rate

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio

+ References

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Stock-Based Compensation - Performance Equity Plan and Accounting for Stock Awards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 31, 2023	May 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	$ 7.2	$ 7.9	$ 9.4
Restricted Shares and Performance-Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 5.3
Period to recognize compensation expense	1 year 10 months 28 days
PNM
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	$ 4.8	5.3	6.4
TNMP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for stock-based arrangements	$ 2.4	$ 2.6	$ 3.0
Performance Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for awards	3 years
Vesting rate	100.00%
Number of shares authorized (in shares)				2,500,000	13,500,000
Charge to share pool for each share awarded	5
Performance Equity Plan \| Nonemployee Members of the Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for awards	1 year