Earnings Per Share - Narrative (Details) - shares		3 Months Ended	6 Months Ended
May 27, 2025	Jun. 30, 2025	Jun. 30, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock in private placement (in shares)		11,600,000	11,600,000
TXNM 2024 ATM Program
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Initial forward price (in shares)	1,104,641	1,100,000	1,100,000

Convertible Debt Exchanged in Private Placement, Principal Amount

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482662/260-10-50-1

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- Definition

Maximum number of shares that could be issued to settle forward contract indexed to equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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