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Revenue and Vendor Concentrations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Revenue, Major Customer [Line Items]
Revenue	$ 9,105	$ 6,440	$ 25,031	$ 17,502
Accounts receivable, net	4,614		4,614		$ 3,937
Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Revenue	$ 3,700	$ 3,600	$ 4,400	$ 6,600
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	11.00%	3.00%	10.00%	1.00%
Customer One [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	22.00%	24.00%	18.00%	27.00%
Customer Two [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	19.00%	20.00%		11.00%
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	$ 600	$ 2,000	$ 600	$ 2,000
Channel Partners [Member] \| Supplier Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage			10.00%