Acquisitions (Details) (USD $) In Thousands	Jul. 31, 2011	Sep. 02, 2010
Summary of purchase price
Stock (1,524,517 shares at $18.82 per share)	$ 28,691
Cash	1,808
Contingent rights	9,486
Advance on purchase price	2,000
Total consideration	$ 41,985	$ 42,000

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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+ Details

- Definition

The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

+ References+ Details