Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 951
Balance at Beginning of Period	32,050
Charged to Costs and Expenses, net of Recoveries	63	$ 436
Balance at End of Period	496	951
Balance at End of Period	34,960	32,050
Inventory Obsolescence Reserve
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	32,050	30,551
Charged to Costs and Expenses	4,529	4,614
(Deductions) and Additions	(1,816)	(3,115)
Balance at End of Period	34,763	32,050
Allowance for Doubtful Accounts on Accounts and Financing Receivables
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	951	3,302
Charged to Costs and Expenses, net of Recoveries	63	436
(Deductions) and Additions	(518)	(2,787)
Balance at End of Period	$ 496	$ 951