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REVENUE - Performance Obligations - Electric Operations (Details) - Physically Delivered Prepaid Power Contract - USD ($) $ in Millions | 3 Months Ended
--- | ---
Sep. 30, 2025 | Jun. 30, 2025
Disaggregation of Revenue [Line Items] |  |
Agreement, term | 5 months | 17 months
Prepaid contract | $ 20.0 | $ 35.0
Incremental borrowing rate | 9.92% | 9.50%

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