Represents percentage of profits interest vested.

No definition available.

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Namespace Prefix:	blgo_
Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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Note 9 - BioLargo Engineering, Science and Technologies, LLC (Details Textual) - shares	1 Months Ended
	Sep. 30, 2017	Sep. 30, 2025	Dec. 31, 2024
Seven Employees Working at BioLargo Engineering, Science & Technologies, LLC [Member]
Percentage of Profits Interests Vested		26.00%	26.00%
Seven Employees Working at BioLargo Engineering, Science & Technologies, LLC [Member] \| Non-Qualified Stock Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	1,750,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	5 years
BioLargo Engineering, Science & Technologies, LLC [Member]
Subsidiary, Ownership Percentage, Parent	100.00%