Summary of Significant Accounting Policies - Impact on Financial Results from Adopting Revenue Recognition Standard (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Product revenue	$ 5,766,532	$ 8,972,112
Support and services revenue	12,071,374	16,188,451
Selling and marketing	4,453,697	6,120,655
Income tax expense	233,288	7,606
Net income (loss)	(906,714)	1,052,401
Net income (loss) attributable to common stockholders	$ (4,465,945)	$ 179,358
Basic net loss per share attributable to common stockholders (in dollars per share)	$ (0.05)	$ 0.00
Diluted net loss per share attributable to common stockholders (in dollars per share)	$ (0.05)	$ 0.00
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Product revenue	$ 9,250,082
Support and services revenue	12,071,374
Selling and marketing	4,461,572
Income tax expense	233,288
Net income (loss)	2,568,961
Net income (loss) attributable to common stockholders	$ (990,270)
Basic net loss per share attributable to common stockholders (in dollars per share)	$ (0.01)
Diluted net loss per share attributable to common stockholders (in dollars per share)	$ (0.01)
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Product revenue	$ (3,483,550)
Support and services revenue	0
Selling and marketing	(7,875)
Income tax expense	0
Net income (loss)	(3,475,675)
Net income (loss) attributable to common stockholders	$ (3,475,675)
Basic net loss per share attributable to common stockholders (in dollars per share)	$ (0.04)
Diluted net loss per share attributable to common stockholders (in dollars per share)	$ (0.04)