v3.25.3

Earnings Per Share - Schedule of Computation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net Earnings Attributable to TXNM	$ 130,710	$ 131,202	$ 161,209	$ 226,441
Average Number of Common Shares:
Outstanding during period (in shares)	107,015	90,200	98,542	90,200
Vested awards of restricted stock (in shares)	346	330	347	306
Average Shares – Basic (in shares)	107,361	90,530	98,889	90,506
Dilutive Effect of Common Stock Equivalents:
Average Shares – Diluted (in shares)	107,417	90,605	99,042	90,552
Net Earnings Per Share of Common Stock:
Basic (in dollars per share)	$ 1.22	$ 1.45	$ 1.63	$ 2.50
Diluted (in dollars per share)	$ 1.22	$ 1.45	$ 1.63	$ 2.50
Restricted Stock
Dilutive Effect of Common Stock Equivalents:
Restricted stock (in shares)	55	53	55	44
TXNM ATM Program
Dilutive Effect of Common Stock Equivalents:
TXNM ATM Programs (in shares)	1	22	98	2

Earnings Per Share, Basic And Diluted, EPS

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TXNM ENERGY INC 10-Q