Segment and Geographic Information and Significant Customers - Additional Information " (Detail) (International Operations)	3 Months Ended	9 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010
International Operations
Segment Reporting Information [Line Items]
Segment revenue	No country outside of the United States provided greater than 10% of our total revenue.	No country outside of the United States provided greater than 10% of our total revenue.	No country outside of the United States provided greater than 10% of our total revenue.		No country outside of the United States provided greater than 10% of our total revenue.
Long-lived or total assets held by segment			No country outside of the United States held greater than 10% of our long-lived or total assets.	No country outside of the United States held greater than 10% of our long-lived or total assets.

Disclosure of the extent of enterprise reliance on its major customers. For example, includes revenues from transactions with a single external customer amounting to 10 percent or more of the entity's revenues, the total amount of revenues from each such customer, and the identity of the segment or segments reporting the revenues. A group of entities that the entity knows to be under common control generally will be considered a single customer for inclusion in this item. The federal government, a state government, a local government (for example, a county or municipality), or a foreign government each will generally be considered as a single customer for inclusion in this item.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 39
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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