Stockholders' Equity - Stock-Based Compensation Expense Related to Stock Options and RSUs (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense included in operating expenses	$ 809,352	$ 922,848	$ 2,494,533	$ 2,667,969
Cost of goods sold [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense included in operating expenses	613		613
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense included in operating expenses	176,148	221,323	543,228	657,014
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense included in operating expenses	130,098	201,690	427,068	579,517
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense included in operating expenses	$ 502,493	$ 499,835	$ 1,523,624	$ 1,431,438