Income and Other Taxes - Continuing Operations before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Domestic	$ 25,744	$ (7,159)	$ (35,100)
Foreign	471	219	(830)
Income (loss) before income tax expense	$ 26,215	$ (6,940)	$ (35,930)