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PROPERTY, PLANT, AND EQUIPMENT - SAMSON AND DELILAH - STORM DAMAGE (Details) - Electric - generation - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2026	Sep. 30, 2025	Jun. 30, 2025
Samson I Solar Energy Center
Property, plant, and equipment
Impairment due to storm damage			$ 2.8
Insurance receivable			2.8
Samson I Solar Energy Center and Delilah Solar Energy
Property, plant, and equipment
Impairment due to storm damage		$ 12.0	$ 8.8
Delilah Solar Energy LLC
Property, plant, and equipment
Impairment due to storm damage	$ 1.7