Summary of Significant Accounting Policies - Summary of Contract Assets and Liabilities (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Total deferred revenue	$ 7,046,760	$ 6,232,687
Less: Long-term deferred revenue	(508,772)	(407,151)
Total current deferred revenue	6,537,988	5,825,536
Contract Assets - Unbilled Receivables [Member]
Total deferred revenue	208,023	251,867
Customer Deposits [Member]
Total deferred revenue	371,000	487,086
Product Shipped, Revenue Deferred [Member]
Total deferred revenue	645,199	645,199
Deferred Service and License Fees [Member]
Total deferred revenue	$ 6,030,561	$ 5,100,402