Document And Entity Information	6 Months Ended
	Mar. 31, 2012	Apr. 30, 2012
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2012
Current Fiscal Year End Date	--09-30
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2012
Entity Registrant Name	OYO GEOSPACE CORP
Entity Central Index Key	0001001115
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		6,372,830