Document and Entity Information	6 Months Ended
Oct. 09, 2011	Nov. 04, 2011 Common Stock	Nov. 04, 2011 Class A Common Stock
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Oct. 09, 2011
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Trading Symbol	BNHN
Entity Registrant Name	BENIHANA INC
Entity Central Index Key	0000935226
Current Fiscal Year End Date	--04-01
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		6,936,775	10,944,177

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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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