CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 28, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Accounts receivable, allowance	$ 241,000	$ 304,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, authorized	3,000	3,000
Preferred stock, issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized	120,000,000	120,000,000
Common stock, issued	88,584,577	80,735,320
Common stock, outstanding	82,053,697	74,008,815
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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-Name Accounting Standards Codification
-Topic 210
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-Section S99
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