Note 2 - Summary of Significant Accounting Policies (Details Textual)	9 Months Ended
Sep. 30, 2017 USD ($)
Allowance for Doubtful Accounts, Premiums and Other Receivables	$ 2,500
Canadian Government Grants [Member]
Number of Grants Received	50
Grants Receivable	$ 1,100,000
Canadian Government Grants [Member] \| Minimum [Member]
Grant Term	180 days
Canadian Government Grants [Member] \| Maximum [Member]
Grant Term	1 year 180 days

Period for grants earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

No definition available.

+ Details

Name:	blgo_GrantTerm
Namespace Prefix:	blgo_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants received.

+ References

No definition available.

+ Details

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Namespace Prefix:	blgo_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),5)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_CounterpartyNameAxis=blgo_CanadianGovernmentGrantsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
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