Business and Basis of Presentation - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Organization And Basis Of Presentation [Line Items]
Cash and cash equivalents	$ 9,116,806	$ 11,687,021	$ 9,116,806	$ 11,687,021	$ 9,221,985	$ 9,195,753
Deferred Revenue	680,000		680,000
Deferred Costs	$ 425,000		$ 425,000
Minimum [Member]
Organization And Basis Of Presentation [Line Items]
Product Sales Right of Return Term			30 days
Maximum [Member]
Organization And Basis Of Presentation [Line Items]
Product Sales Right of Return Term			60 days
Customer One | Accounts Receivable
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage					30.00%
Customer One | Sales Revenue, Net
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage	11.00%		16.00%
Two Customers [Member] | Accounts Receivable
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage			51.00%
Two Customers [Member] | Sales Revenue, Net
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage		31.00%		22.00%