NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Nature of Business (Details)	12 Months Ended
Dec. 31, 2016 item
Nature of business
Number of industry groups in which the entity operates	2
Number of companies collectively referred to as TMC	3
Number of financial instruments transferred from Level 1 to Level 2	0
Number of financial instruments transferred from Level 2 to Level 1	0
Heating Ventilation and Air Conditioning Products [Member]
Nature of business
Number of reportable segments	2
Construction Products [Member]
Nature of business
Number of reportable segments	2

Represents the number of financial instruments transferred into level 2 from level 1 of the fair value hierarchy.

No definition available.

Name:	cuo_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNumberOfFinancialInstrumentsTransferredFromLevel1ToLevel2
Namespace Prefix:	cuo_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of financial instruments transferred into level 1 from level 2 of the fair value hierarchy.

+ References

No definition available.

+ Details

Name:	cuo_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNumberOfFinancialInstrumentsTransferredFromLevel2ToLevel1
Namespace Prefix:	cuo_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of industry groups in which the entity operates.

+ References

No definition available.

+ Details

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

- Definition

Represents the number of companies collectively referred to as TMC.

+ References

No definition available.

+ Details

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

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ProductOrServiceAxis=cuo_HeatingVentilationAndAirConditioningProductsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=cuo_ConstructionProductsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: