Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 2,449	$ 2,516
Balance at Beginning of Period	9,674	6,675
Balance at End of Period	1,395	2,449	$ 2,516
Balance at End of Period	29,614	9,674	6,675
Inventory Obsolescence Reserve
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	9,674	6,675	7,764
Charged to Costs and Expenses	21,472	10,590	3,887
(Deductions) and Additions	(1,532)	(7,591)	(4,976)
Balance at End of Period	29,614	9,674	6,675
Allowance for Doubtful Accounts on Accounts and Financing Receivables
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	2,949	2,516	1,125
Charged to Costs and Expenses	(380)	763	2,147
(Deductions) and Additions	(154)	(330)	(756)
Balance at End of Period	$ 2,415	$ 2,949	$ 2,516