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Revenue and Vendor Concentrations (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 12,831		$ 16,821
Customer Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Revenue	5,500	$ 2,500
Customer Concentration Risk \| Accounts Receivable
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 3,900	$ 1,200
Customer Concentration Risk \| Customer One \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	20.00%	21.00%
Customer Concentration Risk \| Customer Two \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	11.00%
Geographic Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	35.00%	29.00%