SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) - Schedule of Valuation and Qualifying Accounts - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Segment Reporting Information [Line Items]
Balance at Beginning of Year	$ 5,966	$ 4,692	$ 3,905
Recorded to Cost and Expense	(5,920)	1,680	1,554
Accounts Written Off, net	5,219	(406)	(766)
Other	1,143	0	(1)
Balance at End of Year	6,408	5,966	4,692
Inventory valuation [Member]
Segment Reporting Information [Line Items]
Balance at Beginning of Year	16,419	15,338	13,003
Recorded to Cost and Expense	1,924	851	2,820
Accounts Written Off, net	(306)	203	(728)
Other	8,028	27	243
Balance at End of Year	26,065	16,419	15,338
Deferred tax valuation allowance [Member]
Segment Reporting Information [Line Items]
Balance at Beginning of Year	17,466	12,832	10,462
Recorded to Cost and Expense	(8,946)	4,634	2,370
Accounts Written Off, net	0	0	0
Other	0	0	0
Balance at End of Year	8,520	17,466	12,832
Bad debts [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Segment Reporting Information [Line Items]
Balance at Beginning of Year	1,109	1,217	1,628
Recorded to Cost and Expense	(40)	279	349
Accounts Written Off, net	11	(387)	(759)
Other	744	0	(1)
Balance at End of Year	1,824	1,109	1,217
Sales returns and allowances [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Segment Reporting Information [Line Items]
Balance at Beginning of Year	4,857	3,475	2,277
Recorded to Cost and Expense	(5,880)	1,401	1,205
Accounts Written Off, net	5,208	(19)	(7)
Other	399	0	0
Balance at End of Year	$ 4,584	$ 4,857	$ 3,475