Goodwill and Other Intangible Assets - Summary of Gross Carrying Amounts and Accumulated Amortization of Intangible Assets by Major Class (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2023
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 197,080	$ 196,144
Accumulated Amortization	(194,330)	(192,269)
Net Carrying Amount	2,750	3,875
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	107,417	106,713
Accumulated Amortization	(104,667)	(102,942)
Net Carrying Amount	$ 2,750	$ 3,771
Weighted Average Remaining Life (Years)	1 year	1 year 6 months
Technology and Patents
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 89,663	$ 89,431
Accumulated Amortization	(89,663)	(89,327)
Net Carrying Amount	$ 0	$ 104
Weighted Average Remaining Life (Years)	0 years	2 months 12 days