Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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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Percentage of vesting of award under share-based payment arrangement.

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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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Amount of noncash expense for option under share-based payment arrangement.

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STOCK-BASED COMPENSATION (Narrative) (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jun. 25, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 10,000	$ 73,000	$ 67,664	$ 163,508
Minimum [Member] \| CPHC Long Term Incentive Plan (LTI Plan) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
LTI Plan performance period				1 year
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, expiration period				10 years
Share-based compensation, vesting period				42 months
Non-Employee Board Member Stock Options [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, expiration period				10 years
Non-Employee Board Member stock option and Restricted Stock [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage				100.00%
Share-based compensation, vesting period				1 year
Non-Employee Board Member Deferred Stock [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	17,975
Granted, weighted average fair value	$ 11.07
Restricted Stock [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, nonvested number of shares		0		0
Employee Deferred Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	47,000
Granted, weighted average fair value	$ 11.07
Stock-based compensation	$ 466,000
Employee Deferred Stock Award [Member] \| December 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage	60.00%
Employee Deferred Stock Award [Member] \| March 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage	20.00%
Employee Deferred Stock Award [Member] \| March 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage	20.00%