Interim Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 27, 2015	Sep. 26, 2014
Allowance for doubtful accounts	$ (1,046)	$ (1,615)
Class A Common Stock [Member]
Common stock, par value (usd per share)	$ 0.001	$ 0.001
Common stock voting right per share (votes per share)	1	1
Common stock, shares authorized (shares)	500,000,000	500,000,000
Common stock, shares issued (shares)	51,383,446	50,658,627
Common stock, shares outstanding (shares)	51,383,446	50,658,627
Class B Common Stock [Member]
Common stock, par value (usd per share)	$ 0.001	$ 0.001
Common stock voting right per share (votes per share)	10	10
Common stock, shares authorized (shares)	500,000,000	500,000,000
Common stock, shares issued (shares)	51,073,661	51,610,239
Common stock, shares outstanding (shares)	51,073,661	51,610,239

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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