RATE MATTERS - ETT Rate Matters (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Apr. 30, 2026	Mar. 31, 2026
ETT Interim Transmission Rates
Public Utilities, General Disclosures [Line Items]
Requested annual base rate increase (decrease)		$ 1
ETT Interim Transmission Rates \| ETT
Public Utilities, General Disclosures [Line Items]
Equity method investment, ownership percentage		50.00%
2026 ETT Base Rate Case \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested annual base rate increase (decrease)	$ 42
Requested return on equity	10.50%
Requested debt capital structure	55.00%
Requested equity capital structure	45.00%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

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Percentage of public utility's requested debt to capital, including debt and equity.

+ References

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- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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- Definition

Percentage of public utility's requested return on equity.

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