Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Allowance for trade receivables	$ 39,874	$ 36,038
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	34,000,000	34,000,000
Common stock issued (in shares)	25,820,918	25,641,959
Treasury stock (in shares)	1,473,558	868,045

Amount of allowance for credit loss on accounts receivable, classified as current.

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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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