Summary Of Significant Accounting Policies (Allowance for Uncollectible Accounts) (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Allowance for Uncollectible Accounts [Roll Forward]
Balance at Beginning of Period	$ 36,295	$ 40,228
Additions Charged to Costs and Expenses	9,766	10,973
Discounts on Purchased Receivables	468	916
Net Accounts Receivable Written-Off	(6,834)	(3,971)
Balance at End of Period	$ 39,695	$ 48,146