Income Tax Expense - Components Of Income From Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Tax Expense
United States	$ 98,983	$ 90,674	$ 70,214
Foreign	19,964	15,761	10,457
Total income before income taxes	$ 118,947	$ 106,435	$ 80,671