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REVENUE AND VENDOR CONCENTRATIONS (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Revenue, Major Customer [Line Items]
Revenue	$ 21,037	$ 16,109	$ 14,277	$ 12,136	$ 12,904	$ 11,798	$ 11,419	$ 9,269	$ 9,670	$ 9,105	$ 8,522	$ 7,404
Accounts receivable, net	16,821				7,099								$ 16,821	$ 7,099
Sales Revenue, Net \| Customer Concentration Risk
Revenue, Major Customer [Line Items]
Revenue													$ 20,000	$ 10,400	$ 6,300
Sales Revenue, Net \| Customer Concentration Risk \| Customer One
Revenue, Major Customer [Line Items]
Total revenue, percentage													22.00%	23.00%	18.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Two
Revenue, Major Customer [Line Items]
Total revenue, percentage													10.00%
Sales Revenue, Net \| Geographic Concentration Risk \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage													27.00%	14.00%	15.00%
Accounts Receivable \| Customer Concentration Risk
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 5,700				$ 1,300				$ 1,000				$ 5,700	$ 1,300	$ 1,000