Note 12 - Common Stock - Summary of Outstanding Warrants (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Expiration Date	Mar. 26, 2025	Mar. 26, 2025
Exercise Price (in dollars per share)	$ 2,720.00	$ 2,720.00
Shares Outstanding Under Warrants (in shares)	2	2
Warrant One [Member]
Expiration Date	Feb. 17, 2025	Feb. 17, 2025
Exercise Price (in dollars per share)	$ 4,000.00	$ 4,000.00
Shares Outstanding Under Warrants (in shares)	79	79
Warrant Two [Member]
Expiration Date	May 12, 2025	May 12, 2025
Exercise Price (in dollars per share)	$ 4,240.00	$ 4,240.00
Shares Outstanding Under Warrants (in shares)	37	37
Warrant Three [Member]
Expiration Date	Dec. 16, 2025	Dec. 16, 2025
Exercise Price (in dollars per share)	$ 5,600.00	$ 5,600.00
Shares Outstanding Under Warrants (in shares)	31	31
Warrant Four [Member]
Expiration Date	Apr. 01, 2026	Apr. 01, 2026
Exercise Price (in dollars per share)	$ 6,080.00	$ 6,080.00
Shares Outstanding Under Warrants (in shares)	25	25
Warrant Five [Member]
Expiration Date	Jun. 20, 2026	May 11, 2021
Exercise Price (in dollars per share)	$ 4,980.00	$ 7,740.00
Shares Outstanding Under Warrants (in shares)	101	6
Warrant Six [Member]
Expiration Date	May 25, 2027	Jun. 20, 2026
Exercise Price (in dollars per share)	$ 9,500.00	$ 4,980.00
Shares Outstanding Under Warrants (in shares)	223	101
Warrant Seven [Member]
Expiration Date	Nov. 26, 2024	May 25, 2027
Exercise Price (in dollars per share)	$ 18.36	$ 9,500.00
Shares Outstanding Under Warrants (in shares)	989,379	223
Warrant Eight [Member]
Expiration Date	Nov. 26, 2024	Nov. 26, 2024
Exercise Price (in dollars per share)	$ 2.82	$ 6.10
Shares Outstanding Under Warrants (in shares)	285,632	325,632
Warrant Nine [Member]
Expiration Date	Apr. 21, 2025	Nov. 26, 2024
Exercise Price (in dollars per share)	$ 2.82	$ 18.36
Shares Outstanding Under Warrants (in shares)	413,210	989,379
Warrant Ten [Member]
Expiration Date	Jan. 19, 2026	Apr. 21, 2025
Exercise Price (in dollars per share)	$ 3.40	$ 6.37
Shares Outstanding Under Warrants (in shares)	8,104,880	413,210
Warrant Eleven [Member]
Exercise Price (in dollars per share)
Shares Outstanding Under Warrants (in shares)	9,793,599	1,728,725