Investment in ATC and ATC Holdco (Details-2) - ATC [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Schedule of Equity Method Investments [Line Items]
Operating revenues	$ 221,434	$ 206,197	$ 651,584	$ 610,399
Operating expenses	(110,043)	(102,819)	(324,082)	(303,412)
Other income, net	355	701	898	1,657
Interest expense, net	(36,838)	(33,555)	(108,296)	(99,969)
Earnings before members' income taxes	$ 74,908	$ 70,524	$ 220,104	$ 208,675