Income Taxes - Components of Income Before Income Taxes and Equity in Earnings of Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest [Abstract]
Domestic	$ (58,065)	$ (39,392)	$ (88,763)
Foreign	27,632	29,456	39,794
Loss before income taxes	$ (30,433)	$ (9,936)	$ (48,969)