Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 28, 2020	Dec. 28, 2019
Statement of Financial Position [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 786,000	$ 938,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	3,000	3,000
Preferred Stock, Shares Issued	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	120,000,000	120,000,000
Common Stock, Shares, Issued	89,427,296	88,912,796
Common Stock, Shares, Outstanding	82,536,416	82,536,416
Treasury Stock, Shares	4,513,256	4,513,256

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

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