Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 27, 2020	Dec. 29, 2019
Consolidated Balance Sheets
Accounts receivable, allowance for doubtful accounts	$ 3,622	$ 7,341
Notes receivable, less current portion, allowance for doubtful accounts	$ 3,211	$ 3,572
Series B Convertible Preferred Stock, par value	$ 0.01	$ 0.01
Series B Convertible Preferred Stock, shares authorized	260,000.0	260,000.0
Series B Convertible Preferred Stock, shares issued	252,500	252,500
Series B Convertible Preferred Stock, shares outstanding	252,500	252,500
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares issued	45,288,000	44,748,000
Treasury stock, shares	12,743,000	12,854,000

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

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