RELATED PARTY TRANSACTIONS (Details) - USD ($)	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018
RELATED PARTY TRANSACTIONS
Amount paid for service rendered by related party	$ 826,000	$ 474,000
Amount of contingent fee received by related party	$ 13,000	$ 28,000

Represents the amount received by the related party as a contingent fee under the agreement.

No definition available.

Name:	cuo_RelatedPartyTransactionContingentFeeToRelatedParty
Namespace Prefix:	cuo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration