Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jun. 26, 2019	Dec. 26, 2018
Assets [Abstract]
Accumulated depreciation	$ 160,548	$ 226,620
Accumulated amortization	$ 13,282	$ 15,526
Shareholders' deficit
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	135,000	135,000
Common stock, shares issued	109,291	108,585
Common stock, shares outstanding	59,807	61,533
Treasury stock, at cost, shares	49,484	47,052

Accumulated amortization of financing lease ROU assets

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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