Note 8 - Noncontrolling Interest - Clyra Medical - Common Shares Outstanding (Details) - Clyra Medical [Member] - $ / shares	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Options outstanding, balance (in shares)	15,833	14,004	14,004
Balance, Exercise Price Range (in shares)		1.00	1.00
Weighted average exercise price per share, balance (in dollars per share)	$ 5.53	$ 1.00	$ 1.00
Options granted (in shares)	426	648
Granted, Exercise Price (in dollars per share)		$ 1.00
Weighted average exercise price per share, granted (in dollars per share)	$ 148.27	$ 1.00
Options outstanding, balance (in shares)	16,259	14,652	15,833
Balance, Exercise Price Range (in shares)		1.00
Weighted average exercise price per share, balance (in dollars per share)	$ 9.27	$ 1.00	$ 5.53
Minimum [Member]
Balance, Exercise Price Range (in shares)	1.00
Granted, Exercise Price (in dollars per share)	$ 1.00
Balance, Exercise Price Range (in shares)	1.00		1.00
Maximum [Member]
Balance, Exercise Price Range (in shares)	310
Granted, Exercise Price (in dollars per share)	$ 271
Balance, Exercise Price Range (in shares)	310		310