Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Current federal	$ 8,377	$ 0	$ 0
Current state	5,101	1,896	4,859
Deferred federal	6,317	18,997	47,239
Deferred state	(885)	3,065	1,173
Total expense from income taxes	$ 18,910	$ 23,958	$ 53,271