OUR BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)	12 Months Ended
Sep. 30, 2017 USD ($) criteria	Sep. 30, 2016 USD ($)
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Impairment charges	$ 0
Grants received in period	0
Grant proceeds	$ 200,000	$ 400,000
Capital leases, number of key criteria \| criteria	4
Capital lease criteria, lease term to economic life, ratio	75.00%
Capital lease criteria, minimum lease payments to fair value, ratio	90.00%
Material Management
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Maximum percentage of total revenue	5.00%	5.00%

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Capital Leases, Number Of Key Criteria

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The maximum percentage of revenue generated by particular arrangement total net revenue from the sale of goods as of year end.

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Total carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income in future periods and obligations not separately disclosed in the balance sheet (other liabilities).

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

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