BUSINESS SEGMENT INFORMATION, , Entity Wide Information (Details) (USD $)	3 Months Ended												12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012		Mar. 31, 2012	Dec. 31, 2013 Customer		Dec. 31, 2012 Customer		Dec. 31, 2011 Customer
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales	$ 91,016,000	$ 101,164,000	[1]	$ 93,981,000	[1]	$ 63,028,000	$ 71,752,000	[2]	$ 76,059,000	$ 73,222,000	[2]	$ 65,561,000	$ 349,189,000	[3]	$ 286,594,000	[3]	$ 295,121,000
Long-lived Assets by Geographic Location [Abstract]
Long-Lived Assets	54,344,000						47,512,000						54,344,000		47,512,000
Revenue, Major Customer [Line Items]
Number of customers representing sales in excess of ten percent													2		2		2
Revenue from major customers, percentage (in hundredths)													29.60%		24.60%		22.30%
Two Customers [Member]
Revenue, Major Customer [Line Items]
Revenue from major customers													103,300,000		70,600,000		65,700,000
TRP [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													66,100,000
Array [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													2,100,000
Fibreco and Bel Power Europe [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													10,700,000		3,100,000
Interconnect [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													111,653,000		109,245,000		107,346,000
Magnetics [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													170,166,000		100,529,000		87,104,000
Modules [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													55,967,000		66,663,000		90,475,000
Circuit protection [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													11,403,000		10,157,000		10,196,000
North America [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													128,472,000		138,966,000		149,114,000
Asia [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													225,151,000		167,756,000		177,815,000
Long-lived Assets by Geographic Location [Abstract]
Percentage of identifiable assets (in hundredths)	40.00%												40.00%
Europe [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													40,742,000		33,329,000		34,597,000
Intergeographic revenues [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													(45,176,000)		(53,457,000)		(66,405,000)
United States [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													116,548,000		126,469,000		134,804,000
Long-lived Assets by Geographic Location [Abstract]
Long-Lived Assets	30,102,000						27,552,000						30,102,000		27,552,000
Macao [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													193,647,000		128,319,000		126,941,000
Germany [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													16,585,000		14,165,000		17,937,000
United Kingdom [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													16,538,000		13,203,000		11,927,000
Italy [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													3,252,000		1,083,000		0
Sweden [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													4,000		57,000		0
Czech Republic [Member]
Net Sales To External Customers By Geographic Area And Major Product Line [Abstract]
Consolidated net sales													2,615,000		3,298,000		3,512,000
People's Republic of China (PRC) [Member]
Long-lived Assets by Geographic Location [Abstract]
Long-Lived Assets	20,985,000						16,622,000						20,985,000		16,622,000
All other foreign countries [Member]
Long-lived Assets by Geographic Location [Abstract]
Long-Lived Assets	$ 3,257,000						$ 3,338,000						$ 3,257,000		$ 3,338,000

[1] The net earnings for the quarters ended June 30, 2013 and September 30, 2013 have been restated to include the effects of measurement period adjustments related to the acquisitions of TRP and Array. These measurement period adjustments reduced the previously-reported net earnings by $0.7 million and $0.5 million for the quarters ended June 30, 2013 and September 30, 2013, respectively, and primarily related to the step-up of inventory to fair value, and higher depreciation and amortization expense related to the appraised fair values of property, plant and equipment, and the various intangible assets as further described in Note 2.

[2] The net loss for the quarter ended December 31, 2012 includes $3.1 million of restructuring charges primarily related to severance charges and the write-down of assets associated with the closure of the Company’s Vinita, Oklahoma manufacturing facility.

[3] Quarterly amounts of earnings per share may not agree to the total for the year due to rounding.