Note 12 - Commitments and Contingencies - Minimum Lease Payments (Details)	Dec. 31, 2019 USD ($)
Year ending December 31, 2020	$ 176,000
Year ending December 31, 2021	180,000
Year ending December 31, 2022	181,000
Year ending December 31, 2023	122,000
Year ending December 31, 2024	71,000
Total	710,000
BioLargo/ONM Lease [Member]
Year ending December 31, 2020	111,000
Year ending December 31, 2021	115,000
Year ending December 31, 2022	118,000
Year ending December 31, 2023	122,000
Year ending December 31, 2024	71,000
Total	537,000
BLEST Lease [Member]
Year ending December 31, 2020	65,000
Year ending December 31, 2021	65,000
Year ending December 31, 2022	43,000
Year ending December 31, 2023
Year ending December 31, 2024
Total	$ 173,000

Amount of lessee's undiscounted obligation for lease payments for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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