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Revenue and Vendor Concentrations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Revenue, Major Customer [Line Items]
Revenue	$ 8,522	$ 5,672	$ 15,926	$ 11,062
Accounts receivable, net	2,492		2,492		$ 3,937
Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Revenue	$ 2,100	$ 2,300	$ 3,900	$ 4,400
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	10.00%	4.00%	10.00%	3.00%
Customer One [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	15.00%	29.00%	13.00%	29.00%
Customer Two [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage	11.00%	11.00%	12.00%	11.00%
Major Customers [Member] \| Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 100	$ 2,000	$ 100	$ 2,000
Channel Partners [Member] \| Supplier Concentration Risk [Member] \| Sales Revenue Net [Member]
Revenue, Major Customer [Line Items]
Total revenue, percentage			10.00%