CAPITAL LEASES - Future Minimum Lease Payments For Capital Leases (Parenthetical) (Detail)	12 Months Ended
Dec. 31, 2016
Future Minimum Lease Payments For Capital Leases [Line Items]
Present Value of Future Minimum Lease Payments Average Interest Rate	2.40%

Present value of future minimum lease payments average interest rate.

No definition available.

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Namespace Prefix:	cui_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration