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Revenue and Vendor Concentrations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Revenue, Major Customer [Line Items]
Revenue	$ 9,269	$ 7,404
Accounts receivable, net	5,544		$ 4,949
Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Revenue	$ 3,900	$ 3,700
Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	10.00%	10.00%
Geographic Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	25.00%	10.00%
Customer One [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	31.00%	20.00%
Customer Two [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	11.00%	19.00%
Customer Three [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage		12.00%
Major Customers [Member] \| Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 2,500	$ 2,300
Channel Partners [Member] \| Supplier Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	10.00%