SUMMARY OF CRITICAL ACCOUNTING POLICIES AND ESTIMATES - Summary of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 12,426,704	$ 10,895,044	$ 16,295,062
Restricted cash	100,125	100,125	100,134
Cash and cash equivalents and restricted cash as shown in the consolidated statements of cash flows	$ 12,526,829	$ 10,995,169	$ 16,395,196	$ 4,199,825