QUARTERLY FINANCIAL INFORMATION - UNAUDITED (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended													12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	[1]	Dec. 31, 2015		Sep. 30, 2015		Jun. 30, 2015		Mar. 31, 2015	[1]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information [Line Items]
Total revenue	$ 19,403	$ 23,257	$ 23,140	$ 20,661		$ 21,886	[2]	$ 24,845	[2]	$ 22,872	[2]	$ 16,637	[2]	$ 86,461	$ 86,240	$ 76,045
Total cost of revenue	12,931	14,660	13,983	12,626		13,427	[2],[3]	15,506	[2],[3]	14,599	[2],[3]	10,416	[2],[3]	54,200	53,948	47,494
Gross profit	$ 6,472	$ 8,597	$ 9,157	$ 8,035		$ 8,459		$ 9,339		$ 8,273		$ 6,221		32,261	32,292	28,551
Gross profit percent	33.00%	37.00%	40.00%	39.00%		39.00%		38.00%		36.00%		37.00%
Selling, general and administrative	$ 7,912	$ 8,080	$ 9,009	$ 9,238		$ 8,503		$ 7,941		$ 7,894		$ 8,685		34,239	33,023	25,924
Depreciation and amortization	557	585	616	608		635	[3]	632	[3]	609	[3]	986	[3]
Research and development	471	512	527	506		342		532		531		443		2,016	1,848	1,306
Bad debt	44	0	42	7		(9)		67		54		83		93	195	(39)
Other operating expenses	52	5	0	0		56		0		0		2
Operating (loss)	(2,564)	(585)	(1,037)	(2,324)		(1,068)		167		(815)		(3,978)		(6,510)	(5,694)	(2,896)
Net (loss)	$ (2,610)	$ (507)	$ (1,481)	$ (2,668)		$ (1,348)		$ (59)		$ (504)		$ (4,076)		$ (7,266)	$ (5,987)	$ (2,801)
Earnings (loss) per common share:
Basic income (loss) per common share	$ (0.12)	$ (0.02)	$ (0.07)	$ (0.13)		$ (0.06)		$ (0.00)		$ (0.02)		$ (0.20)		$ (0.35)	$ (0.29)	$ (0.14)
Diluted income (loss) per common share	$ (0.12)	$ (0.02)	$ (0.07)	$ (0.13)		$ (0.06)		$ (0.00)		$ (0.02)		$ (0.20)		$ (0.35)	$ (0.29)	$ (0.14)
Basic and diluted weighted average common shares outstanding	20,916,559	20,906,781	20,889,052	20,878,549		20,807,205		20,802,217		20,786,081		20,774,000		20,897,812	20,792,494	20,658,634

[1] On March 5, 2015, the Company closed on an Asset Purchase Agreement to acquire certain assets and assume certain liabilities of Tectrol, Inc., a Toronto, Canada corporation. The acquisition was effective March 1, 2015 and results are included from that date in the Company’s Power and Electromechanical segment.

[2] Revenue and cost of revenue have been revised. Immaterial revisions made to 2015 amounts were related to sales of raw material components to a vendor that in turn, sold finished goods inventory to the Company that included the raw material components that we had sold to the vendor. Revisions decreased total revenue and total cost of revenue for the first, second third and fourth quarters of 2015 by $216 thousand, $100 thousand, $83 thousand and $28 thousand, respectively. These revisions had no effect on gross profit, operating (loss) or net (loss). For more information see Note 2. Summary of Significant Accounting Policies - Revisions.

[3] In the fourth quarter of 2015, the Company reclassified $133 thousand of depreciation and amortization at CUI-Canada to cost of revenue. During 2016, for comparative purposes this 2015 adjustment was reclassified according to the quarter when the original expense was recorded. Accordingly, in the first, second, third and fourth quarters of 2015, $12 thousand, $37 thousand, $41 thousand and $43 thousand, respectively, of depreciation and amortization was reclassified to cost of revenue and the $133 thousand adjustment representing the full year reclassification was removed from the fourth quarter 2015 presentation.