Acquisitions.

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Shares acquire price per share.

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Discount rate of applied to developed product technology and in process research and development.

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The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

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Acquisitions (Details Textuals) (USD $)	12 Months Ended
Acquisitions (Details Textuals) (USD $)	Jul. 31, 2011	Dec. 03, 2010	Sep. 02, 2010
Business Acquisition [Line Items]
Total purchase price	$ 41,985,000		$ 42,000,000
Acquisitions Details (Textuals) [Abstract]
Number of shares issued in acquisition	1,524,517
Shares issued price per share	$ 18.82
Weighted average useful life of purchased intangible assets	5.2
Discount rate of applied to developed product technology and IPR&D	16.00%
Acquisition-related costs incurred	700,000
Contingent rights	9,486,000
Maximum contingent rights liability	13,500,000
Goodwill	24,842,000	600,000
Amigopod [Member]
Business Acquisition [Line Items]
Total purchase price		$ 3,000,000