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Gross number of share options (or share units) granted during the period.

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

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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Maximum number of shares an individual may be granted in options to purchase during any fiscal year.

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SHAREHOLDERS' EQUITY - General Information (Details) - shares	1 Months Ended	12 Months Ended
	Jun. 30, 2006	Dec. 27, 2024	Dec. 29, 2023	Dec. 30, 2022	Dec. 27, 2019	Dec. 29, 2017	Dec. 30, 2016	Dec. 28, 2012	Dec. 31, 2010	Dec. 31, 2021	Jun. 30, 2008	Mar. 31, 2008	Dec. 28, 2007
Share-based Compensation
Options, granted (in shares)		0	0	0
Options outstanding (in shares)		551,000	787,000	816,000						849,000
2006 Stock Incentive Plan
Share-based Compensation
Number of shares of common stock reserved for issuance (in shares)	300,000
Options outstanding (in shares)		0
2008 Performance Incentive Plan
Share-based Compensation
Number of shares of common stock reserved for issuance (in shares)		1,138,000										450,000
Number of shares available for grant (in shares)											182,735
Number of additional shares authorized (in shares)		675,000	750,000	478,000	955,000	875,000	500,000	500,000	350,000
Employee Stock Option \| 2008 Performance Incentive Plan
Share-based Compensation
Maximum number of shares a participant may be granted in options to purchase during fiscal year		300,000
Incentive Stock Options \| 2008 Performance Incentive Plan
Share-based Compensation
Options outstanding (in shares)		24,000
Non Statutory Stock Options \| 2006 Stock Incentive Plan
Share-based Compensation
Expiration period from date of grant	10 years
Non Statutory Stock Options \| 2008 Performance Incentive Plan
Share-based Compensation
Expiration period from date of grant		10 years
Options outstanding (in shares)		527,000
Restricted Stock
Share-based Compensation
Other than options, outstanding (in shares)		146,000	171,000	135,000						110,000
Restricted Stock \| 2008 Performance Incentive Plan
Share-based Compensation
Other than options, outstanding (in shares)		146,000
Restricted Stock Units (RSUs)
Share-based Compensation
Other than options, outstanding (in shares)		70,000
Restricted Stock Units (RSUs) \| 2008 Performance Incentive Plan
Share-based Compensation
Other than options, outstanding (in shares)		70,000
Performance Shares
Share-based Compensation
Other than options, outstanding (in shares)		169,000	130,000	66,000						224,000
Performance Shares \| 2008 Performance Incentive Plan
Share-based Compensation
Other than options, outstanding (in shares)		168,000
Employee Stock
Share-based Compensation
Number of shares of common stock reserved for issuance (in shares)		1,925,000											300,000
Number of shares available for grant (in shares)		816,000
Purchase price per share as a percentage of fair market value		85.00%
Number of additional shares authorized (in shares)			800,000			825,000
Employee Stock \| Minimum
Share-based Compensation
Percentage of participant's earnings to be contributed under a share based compensation plan		1.00%
Employee Stock \| Maximum
Share-based Compensation
Percentage of participant's earnings to be contributed under a share based compensation plan		10.00%