LEGAL PROCEEDINGS (Details)	3 Months Ended
Mar. 28, 2020 item
LEGAL PROCEEDINGS
Number of proceedings having material adverse effect on the consolidated results of operations, cash flows or financial condition	0

Represents the number of events occurred that would have a material effect on the estimated proved reserves.

No definition available.

Name:	cuo_LossContingencyNumberOfClaimsArisingInPeriodHavingMaterialEffectOnFinancialCondition
Namespace Prefix:	cuo_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration