SHAREHOLDERS' EQUITY AND STOCK-BASED COMPENSATION (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Income Per Share
Weighted-average number of common shares used in basic income per share	40,663	41,796	40,590	43,024
Dilutive securities - Restricted stock shares and restricted stock units	0	0	0	748
Weighted-average number of common shares and dilutive securities used in diluted income per share	40,663	41,796	40,590	43,772
Stock options
Stock-based Compensation
Options outstanding (in shares)		0		0
Restricted stock shares/units
Stock-based Compensation
Number of options or units that were excluded from the computation of diluted income per share	342	568	315	58
Restricted Stock And Restricted Stock Units that did not Meet Required Market Thresholds for Vesting
Stock-based Compensation
Number of options or units that were excluded from the computation of diluted income per share	536	173	541
Stock options
Stock-based Compensation
Number of options or units that were excluded from the computation of diluted income per share	323		323

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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Number of options outstanding, including both vested and non-vested options.

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