Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 1,453
Balance at Beginning of Period	30,551
Charged to Costs and Expenses, net of Recoveries	436	$ 1,009
Balance at End of Period	951	1,453
Balance at End of Period	32,050	30,551
Inventory Obsolescence Reserve
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	30,551	29,614
Charged to Costs and Expenses	4,614	4,353
(Deductions) and Additions	(3,115)	(3,416)
Balance at End of Period	32,050	30,551
Allowance for Doubtful Accounts on Accounts and Financing Receivables
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	3,302	2,415
Charged to Costs and Expenses, net of Recoveries	436	1,009
(Deductions) and Additions	(2,787)	(122)
Balance at End of Period	$ 951	$ 3,302