Consolidated Balance Sheets - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash	$ 190,682,109	$ 219,966,167
Prepaid and other current assets	137,181	413,095
Total current assets	190,819,290	220,379,262
Equipment, net	30,422	30,623
Other assets	139,875	139,875
Total assets	190,989,587	220,549,760
Current liabilities:
Accounts payable	9,363,225	10,943,325
Accrued expenses and other current liabilities	7,091,470	10,949,128
Loan payable, current portion	6,547,261	2,602,292
Total current liabilities	23,001,956	24,494,745
Loan payable, long-term	13,744,321	17,332,626
Total liabilities	36,746,277	41,827,371
Stockholders' equity:
Preferred stock, $0.0001 par value per share (10,000,000 shares authorized, none issued and outstanding at March 31, 2020 and December 31, 2019, respectively)
Common stock, $0.0001 par value per share (150,000,000 shares authorized, 37,075,422 and 36,933,217 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively)	3,726	3,693
Additional paid-in capital	380,946,215	354,614,189
Accumulated deficit	(226,706,631)	(175,895,493)
Total stockholders' equity	154,243,310	178,722,389
Total liabilities and stockholders' equity	$ 190,989,587	$ 220,549,760