INVESTMENTS AND FAIR VALUE MEASUREMENTS - Additional Information (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($)
Contingent Consideration Classified as Equity [Member]
Payments On Contingent Consideration	$ 61

The cash outflow for the payment of contingent consideration during the reporting period.

No definition available.

Name:	cui_PaymentsOnContingentConsideration
Namespace Prefix:	cui_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration