Note 10 - BioLargo Energy Technologies, Inc. (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2024	Jun. 30, 2025	Jan. 01, 2023
BioLargo Energy Technologies, Inc (BETI) [Member]
Stock Issued During Period, Shares, New Issues (in shares)	20,000	0
Shares Issued, Price Per Share (in dollars per share)	$ 2.5
Proceeds from Issuance or Sale of Equity	$ 50,000
Stock Conversion, Discount on Volume Weighted Average Price	20.00%
Shares, Outstanding (in shares)		9,487,000
BioLargo Energy Technologies, Inc (BETI) [Member]
Investment Owned, Balance, Shares (in shares)		9,070,000	9,000,000