Consolidated Statements of Stockholders' Equity (Parentheticals) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Warrants at $3.00 Per Share [Member]
Warrants, exercise price (in dollars per share)		$ 3.00
Warrants at $5.00 Per Share [Member]
Warrants, exercise price (in dollars per share)		5.00
Warrants at $6.00 Per Share [Member]
Warrants, exercise price (in dollars per share)		6.00
Warrants at $6.50 Per Share [Member]
Warrants, exercise price (in dollars per share)	$ 6.50	6.50
Warrants at $8.125 Per Share [Member]
Warrants, exercise price (in dollars per share)	$ 8.125
Common stock and warrants, price per share (in dollars per share)		$ 6.00