ORGANIZATION AND DESCRIPTION OF BUSINESS (Details) - Endo [Member] - USD ($)	1 Months Ended
Feb. 29, 2016	Mar. 31, 2019	Feb. 01, 2016
Organization and Description of Business [Abstract]
Deferred revenue			$ 8,250,000
Proceeds from licensing agreement	$ 8,250,000
Opt-in fee receivable for each indication		$ 500,000
Regular opt-in fee receivable for each indication		$ 750,000

The opt in fee receivable for each indication during the period.

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- References

No definition available.

+ Details

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- Definition

The regular opt in fee receivable for each indication during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	bstc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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Balance Type:	credit
Period Type:	instant

- Definition

Cash received from licensees for license fees during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

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