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v3.26.1

Investment in ATC and ATC Holdco (Details-2) - ATC [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Schedule of Equity Method Investments [Line Items] |  |  |  |
Operating revenues | $ 274,048 | $ 241,227 | $ 539,307 | $ 476,156
Operating expenses | (129,636) | (117,564) | (257,041) | (234,309)
Other income, net | 1,228 | 550 | 1,928 | 633
Interest expense, net | (45,925) | (43,254) | (90,401) | (82,447)
Earnings before members' income taxes | $ 99,715 | $ 80,959 | $ 193,793 | $ 160,033

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