Overview and Summary Of Significant Accounting Policies Schedule of Accounts and notes receivable (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables from Customers	$ 166,812		$ 125,715
Unbilled Receivables, Current	108,806		91,463
Receivables from Stockholder	6,434		5,178
Other Receivables	15,373		13,848
Accounts Receivable, Allowance for Credit Loss	(3,765)		(2,283)
Accounts Receivable, after Allowance for Credit Loss, Current	293,660		233,921
Accounts Receivable, Allowance for Credit Loss, Current	3,765	$ 1,063	$ 2,283	$ 1,117
Accounts Receivable, Credit Loss Expense (Reversal)	1,022	983
Accounts Receivable, Allowance for Credit Loss, Writeoff	(159)	(1,522)
Accounts Receivable, Allowance for Credit Loss, Recovery	$ 619	$ 485