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Proceeds From Divestiture Of Interest In Consolidated Subsidiaries, Net

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Public Utilities, Contribution To Construction Activities

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Aggregate dividends declared during the period for each share of common stock outstanding.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries or equity method investee.

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The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits.

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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Significant Accounting Policies and Responsibility for Financial Statements (Details) - USD ($)	3 Months Ended				9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Aug. 02, 2024	Aug. 01, 2024
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)	200,000,000				200,000,000		200,000,000
Payment defaults under agreements	$ 0				$ 0
Gain on sale of NMRD					$ 0	$ 4,449,000
Investment tax credit						$ 15,700,000
Dividends declared per common share (in dollars per share)	$ 0.4075	$ 0.4075	$ 0.3875	$ 0.3875	$ 1.2225	$ 1.1625
Dividends declared on common stock	$ 85,884,000		$ 69,906,000		$ 124,644,000	$ 104,858,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| NMRD
Subsequent Event [Line Items]
Proceeds from interests						117,000,000
PNMR Development \| NMRD
Subsequent Event [Line Items]
Contribution to construction activities						12,600,000
TXNM
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)								200,000,000	120,000,000
Equity contribution from parent	0		0		250,000,000	0
Dividends declared on common stock	$ 0		0		$ 0	0
Public Service Company of New Mexico
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)	40,000,000				40,000,000		40,000,000
Equity contribution from parent	$ 0		0		$ 0	55,000,000
Dividends declared on common stock	$ 0		$ 0		$ 0	$ 0