General	12 Months Ended
Sep. 30, 2012
General [Abstract]
Organization Consolidation And Presentation Of Financial Statements Disclosure Text Block	1.Business Description and Basis of Presentation MWI Veterinary Supply, Inc. is a leading distributor of animal health products to veterinarians in the United States and United Kingdom. We sell our products to veterinarians in both the companion and production animal markets. We operate fourteen distribution centers located across the United States and one distribution center in the United Kingdom.

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

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