Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 26, 2021	Dec. 27, 2020
Consolidated Balance Sheets
Accounts receivable, allowance for doubtful accounts	$ 2,364	$ 3,622
Notes receivable, less current portion, allowance for doubtful accounts	$ 1,500	$ 3,211
Series B Convertible Preferred Stock, par value	$ 0.01	$ 0.01
Series B Convertible Preferred Stock, shares authorized	0	260,000.0
Series B Convertible Preferred Stock, shares issued	0	252,500
Series B Convertible Preferred Stock, shares outstanding	0	252,500
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares issued	49,002,000	45,288,000
Treasury stock, shares	13,205,000	12,743,000

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

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