Earnings Per Share (Schedule Of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 27, 2016	Mar. 29, 2015
Earnings Per Share [Abstract]
Net loss available to common stockholders	$ (32,521)	$ (2,559)
Weighted-average number of common shares outstanding (shares)	41,485	41,852
Shares issuable under deferred compensation agreements (shares)	811	805
Basic weighted-average number of common shares outstanding (shares)	42,296	42,657
Common shares assumed upon exercise of stock options and awards (shares)	0	0
Unvested shares issuable under deferred compensation arrangements (shares)	0	0
Dilutive weighted-average number of common shares outstanding (shares)	42,296	42,657
Basic (loss) earnings per share (USD per share)	$ (0.77)	$ (0.06)
Diluted (loss) earnings per share (USD per share)	$ (0.77)	$ (0.06)

Shares Issuable Under Deferred Compensation Arrangements, Diluted

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Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic).

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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