Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Sales return allowance	$ 454,730	$ 488,200
Technology fees	450,000	450,000
Professional services	343,000	390,800
Advertising and promotion	335,600	28,100
Warranty reserve	112,008	45,879
Other	215,724	245,752
Accrued expenses	$ 1,911,062	$ 1,648,731