CONSOLIDATED CONDENSED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 25, 2021	Dec. 26, 2020
CONSOLIDATED BALANCE SHEETS
Receivables, allowance for doubtful accounts	$ 1,200	$ 800
Unamortized debt issuance costs - Current	17,400	13,900
Unamortized debt issuance costs - Noncurrent	$ 65,500	$ 54,800
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,623,538	3,756,028
Common stock, shares outstanding	3,623,538	3,756,028

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

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Face amount per share of no-par value common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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