SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended						12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015		Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Significant Accounting Policies [Line Items]
Number of common shares obtained							352,589
Allowance for doubtful accounts		$ 90					$ 151	$ 90
Cash and cash equivalents in foreign accounts		200					200	200
Billings in excess of cost		2,190					$ 1,977	$ 2,190
Concentration risk, percentage							100.00%	100.00%		100.00%
Advertising Costs Offset Against Revenue							$ 300	$ 400		$ 300
Costs in Excess of Billings, Current		1,571					2,735	1,571
Product Warranty Accrual		50					52	50
Advertising Expense							$ 1,700	$ 1,400		1,300
Stock Issued During Period, Shares, Issued for Services							25,811	61,548
Shipping and Handling Revenue							$ 23	$ 48		42
Cash, FDIC Insured Amount		600					800	600
Accrued Liabilities, Current		5,222					4,542	5,222
Accounts Payable, Trade, Current		1,900					1,100	1,900
Derivative, Gain on Derivative							113	20
Derivative, Loss on Derivative										172
Investment Interest Rate Percentage	5.00%
Equity Method Investment, Ownership Percentage											8.50%	8.94%
Investment Income, Interest							19
Inventory Valuation Reserves		483	[1]				774	483	[1]
Cash Reclassified To Increase Decrease In Accounts Payable								76		20
Cash Reclassified To Increase Decrease In Accrued Expenses								66
Reclassification Increase Decrease in Inventory to Inventory Reserve								97
Increase Decrease In Property And Equipment Due To Cash Reclassification								92		11
Increase Decrease In Investments And Other Intangible Assets With Offsetting Cash Reclassification								50		9
Increase Decrease In Sales And Cost Of Sales Related To Inventory		28		$ 83	$ 100	$ 216		427
Reclassifications Of Use Of Cash Prepaid Expenses To Inventory							$ 246
Reclassifications Of Prepaid Expenses To Inventory								246
Prepaid Expenses [Member]
Significant Accounting Policies [Line Items]
Inventory Valuation Reserves		97						97
Inventory, Raw Materials, Gross		246						246
Distributor One
Significant Accounting Policies [Line Items]
Concentration risk, percentage							19.00%
Distributor Two
Significant Accounting Policies [Line Items]
Concentration risk, percentage							10.00%
CUI, Inc
Significant Accounting Policies [Line Items]
Defined Benefit Plan, Contributions by Employer							$ 400	400		300
Defined Benefit Plan Contribution By Employer Percentage							6.00%
Orbital
Significant Accounting Policies [Line Items]
Defined Benefit Plan, Contributions by Employer							$ 300	300		300
Defined Benefit Plan Contribution By Employer Percentage							5.00%
European Foreign Bank
Significant Accounting Policies [Line Items]
Cash, uninsured amount		2,200					$ 1,000	2,200
Japanese Foreign Bank
Significant Accounting Policies [Line Items]
Cash, uninsured amount		200					200	200
Canadian Foreign Bank
Significant Accounting Policies [Line Items]
Cash, uninsured amount		$ 300					100	$ 300
Test Products International Inc [Member]
Significant Accounting Policies [Line Items]
Equity Method Investment, Ownership Percentage		8.50%						8.50%
Notes Receivable, Related Parties	$ 400
Other Segments
Significant Accounting Policies [Line Items]
Depreciation and amortization expense							$ 500	$ 300		$ 200

[1] At December 31, 2015, CUI-Canada inventory reserves of $97 thousand were reclassified from raw materials to inventory reserves and $246 thousand of prepaid expenses at CUI Inc. were reclassified to raw materials inventory.