CESSATION OF MINING AT LEASED PUEBLO GRAVEL SITE (Details) - Pueblo Colorado gravel operations - USD ($)		12 Months Ended
Oct. 16, 2019	Dec. 28, 2019	Sep. 28, 2019
Disposition of assets.
Payment to Valco	$ 9,000,000
Estimated loss on litigation settlement			$ 6,400,000
Third-party appraisal of the property		$ 2,200,000
Loss on litigation settlement		$ 6,800,000

The land value obtained from third party appraisal of the property.

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Amount awarded to other party in judgment or settlement of litigation.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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