Income Taxes - Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Deferred Tax Liabilities, Gross [Abstract]
Depreciation and intangible amortization	$ (97,572)	$ (56,856)
Right-of-use assets	(16,632)	(14,146)
Other liabilities	(317)	(402)
Net unrealized loss	(1,574)	(27,144)
Deferred tax liabilities	$ (116,095)	$ (98,548)