Aggregate number of common shares reserved for future issuance.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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The percentage rate of participant's earnings that may be contributed each payroll period.

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Share-Based Compensation Arrangement by Share-Based Payment Award, Plan, Extension Term

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SHAREHOLDERS' EQUITY - General Information (Details) - shares	1 Months Ended	12 Months Ended
	Jun. 30, 2006	Dec. 30, 2022	Dec. 27, 2019	Dec. 29, 2017	Dec. 30, 2016	Dec. 28, 2012	Dec. 31, 2010	Dec. 31, 2021	Jan. 01, 2021	Jun. 30, 2008	Mar. 31, 2008	Dec. 28, 2007
Share-based Compensation
Options, granted (in shares)		0
Options outstanding (in shares)		816,000	1,124,000					849,000	1,003,000
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
Extension period		3 years	10 years
Number of shares of common stock reserved for issuance (in shares)		392,000									450,000
Number of shares available for grant (in shares)										182,735
Number of additional shares authorized (in shares)		478,000	955,000	875,000	500,000	500,000	350,000
Share-Based Payment Arrangement, 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)		40,000
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)		776,000
Restricted Stock
Share-based Compensation
Other than options, outstanding (in shares)		135,000	58,000					110,000	128,000
Restricted Stock \| 2008 Performance Incentive Plan
Share-based Compensation
Other than options, outstanding (in shares)		135,000
Performance Shares
Share-based Compensation
Other than options, outstanding (in shares)		66,000	431,000					224,000	379,000
Performance Shares \| 2008 Performance Incentive Plan
Share-based Compensation
Other than options, outstanding (in shares)		66,000
Employee Stock
Share-based Compensation
Number of shares of common stock reserved for issuance (in shares)		1,125,000										300,000
Number of shares available for grant (in shares)		364,000
Purchase price per share as a percentage of fair market value		85.00%
Number of additional shares authorized (in shares)				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%