INVENTORIES - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Accrued Inventory Payable	$ 1.3	$ 1.1

It represents the value of accrued inventory payable.

No definition available.

Name:	cui_AccruedInventoryPayable
Namespace Prefix:	cui_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant