Note 9 - Noncontrolling Interest - Clyra Medical Common and Preferred Shares Outstanding (Details) - Clyra Medical Technology Inc [Member]	Dec. 31, 2019 shares
Shares, Outstanding (in shares)	72,663
Biolargo [Member]
Shares, Outstanding (in shares)	26,202
Percent	36.00%
Sanatio [Member]
Shares, Outstanding (in shares)	15,064
Percent	21.00%
Scion Solutions [Member]
Shares, Outstanding (in shares)	15,500	[1]
Percent	21.00%	[1]
Other [Member]
Shares, Outstanding (in shares)	15,897
Percent	22.00%

[1] Does not include an additional 15,500 shares held in escrow subject to performance metrics (see Note 3).