Note 9 - Noncontrolling Interest - Clyra Medical Common and Preferred Shares Outstanding (Details) - Clyra Medical Technology Inc [Member]	Jun. 30, 2021 shares
Shares, Outstanding (in shares)	108,891
Biolargo [Member]
Shares, Outstanding (in shares)	49,207
Percent	45.00%
Sanatio [Member]
Shares, Outstanding (in shares)	18,704
Percent	17.00%
Scion Solutions [Member]
Shares, Outstanding (in shares)	21,700	[1]
Percent	20.00%	[1]
Other [Member]
Shares, Outstanding (in shares)	19,280
Percent	18.00%

[1] The above amounts do not include an additional 9,300 shares held in escrow subject to performance metrics that have not been met.