Document and Entity Information	9 Months Ended
Jun. 30, 2011	Aug. 09, 2011
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Trading Symbol	BASI
Entity Registrant Name	BIOANALYTICAL SYSTEMS INC
Entity Central Index Key	0000720154
Current Fiscal Year End Date	--09-30
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		6,912,511

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The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type is limited to the same value as the supporting SEC submission type, minus any "/A" suffix. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, 497, NCSR, N-CSR, N-CSRS, N-Q, 10-KT, 10-QT, 20-FT, and Other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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