Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Sep. 28, 2018	Sep. 30, 2017	Sep. 29, 2017	Oct. 01, 2016	Sep. 30, 2016	Oct. 02, 2015
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 16,203		$ 16,035		$ 17,028	$ 10,050
Common stock, par value	$ 0.20		$ 0.20		$ 0.20
Common stock, shares authorized	60,000,000		60,000,000
Common stock, shares issued	33,190,467	33,117,473	33,117,473	32,564,252
Treasury stock, shares repurchased	3,737,327	3,135,927	3,135,927	3,135,927

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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-Topic 310
-SubTopic 10
-Section 50
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Face amount or stated value per share of common stock.

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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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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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