SUMMARY OF CRITICAL ACCOUNTING POLICIES AND ESTIMATES- Summary of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash and cash equivalents	$ 498,219	$ 1,249,831	$ 1,618,830
Restricted cash	100,007	1,600,000	100,000
Cash and cash equivalents and restricted cash as shown in the consolidated statements of cash flows	$ 598,226	$ 2,849,831	$ 1,718,830	$ 1,105,787