Income and Other Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 42	$ (139)
Effective tax rate on continuing operations	0.10%	(0.30%)
Portion of operating loss carryforward subject to limitation	$ 111,600
Portion of operating loss carryforward not subject to limitation	279,900
Foreign Income And Research And Development Credit
Operating Loss Carryforwards [Line Items]
Tax credit	300
Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	391,500	$ 424,900
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 95,000