DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ / shares in Units, $ in Thousands			3 Months Ended										12 Months Ended
	Sep. 12, 2012	Jul. 31, 2012	Dec. 31, 2015 USD ($) $ / shares	Sep. 30, 2015 USD ($) $ / shares	Jun. 30, 2015 USD ($) $ / shares	Mar. 31, 2015 USD ($) $ / shares	[1]	Dec. 31, 2014 USD ($) $ / shares	[2]	Sep. 30, 2014 USD ($) $ / shares	Jun. 30, 2014 USD ($) $ / shares	Mar. 31, 2014 USD ($) $ / shares	Dec. 31, 2015 USD ($) Segment $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Jul. 25, 2014	Jun. 19, 2014	Aug. 20, 2013	Mar. 29, 2013
DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Number of reportable segments | Segment													3
Effects of Foreign Currency [Abstract]
Net currency exchange gains													$ 5,100	$ 4,300
Net currency exchange losses															$ (600)
Numerator [Abstract]
Net earnings			$ 2,895	$ 4,920	$ 6,062	$ 5,320		$ 1,774		$ 1,261	$ 3,065	$ 2,503	19,197	8,603	15,908
Undistributed earnings													15,962	5,416	12,810
Undistributed earnings allocation - basic and diluted [Abstract]
Undistributed earnings													15,962	5,416	12,810
Net earnings allocation - basic and diluted [Abstract]
Net earnings			$ 2,895	$ 4,920	$ 6,062	$ 5,320		$ 1,774		$ 1,261	$ 3,065	$ 2,503	19,197	8,603	15,908
Research and Development ("R&D") [Abstract]
Research and development costs													$ 27,700	21,500	14,100
Machinery and Equipment [Member] | Minimum [Member]
Depreciation [Abstract]
Property, plant and equipment, useful life													3 years
Machinery and Equipment [Member] | Maximum [Member]
Depreciation [Abstract]
Property, plant and equipment, useful life													15 years
Buildings and Leasehold Improvements [Member] | Minimum [Member]
Depreciation [Abstract]
Property, plant and equipment, useful life													3 years
Buildings and Leasehold Improvements [Member] | Maximum [Member]
Depreciation [Abstract]
Property, plant and equipment, useful life													39 years
Class A [Member]
Numerator [Abstract]
Net earnings													$ 3,331	1,492	2,868
Less dividends declared													522	522	522
Undistributed earnings													2,809	970	2,346
Undistributed earnings allocation - basic and diluted [Abstract]
Undistributed earnings													2,809	970	2,346
Net earnings allocation - basic and diluted [Abstract]
Net earnings													$ 3,331	$ 1,492	$ 2,868
Weighted average shares outstanding [Abstract]
Weighted average shares outstanding (in shares) | shares													2,175	2,175	2,175
Net earnings per share [Abstract]
Common share - basic and diluted (in dollars per share) | $ / shares			$ 0.23	$ 0.39	$ 0.49	$ 0.43		$ 0.14		$ 0.10	$ 0.25	$ 0.20	$ 1.53	$ 0.69	$ 1.32
Class B [Member]
Earnings Per Share [Line Items]
Dividend rate Class B common stock in excess of dividend rate of Class A common stock													5.00%	5.00%	5.00%
Undistributed earning allocation rate of Class B common stock in excess of Class A common stock, percentage													5.00%	5.00%	5.00%
Numerator [Abstract]
Net earnings													$ 15,866	$ 7,111	$ 13,040
Less dividends declared													2,713	2,665	2,576
Undistributed earnings													13,153	4,446	10,464
Undistributed earnings allocation - basic and diluted [Abstract]
Undistributed earnings													13,153	4,446	10,464
Net earnings allocation - basic and diluted [Abstract]
Net earnings													$ 15,866	$ 7,111	$ 13,040
Weighted average shares outstanding [Abstract]
Weighted average shares outstanding (in shares) | shares													9,698	9,491	9,240
Net earnings per share [Abstract]
Common share - basic and diluted (in dollars per share) | $ / shares			$ 0.25	$ 0.42	$ 0.52	$ 0.45		$ 0.15		$ 0.11	$ 0.27	$ 0.22	$ 1.64	$ 0.75	$ 1.41
Powerbox [Member]
Business Acquisition [Line Items]
Acquisition date	Sep. 12, 2012
Acquisition of issued and outstanding capital stock, percentage	100.00%
Fibreco [Member]
Business Acquisition [Line Items]
Acquisition date		Jul. 31, 2012
Acquisition of issued and outstanding capital stock, percentage		100.00%
Array [Member]
Business Acquisition [Line Items]
Acquisition date													Aug. 20, 2013
Acquisition of issued and outstanding capital stock, percentage																		100.00%
TRP [Member]
Business Acquisition [Line Items]
Acquisition date													Mar. 29, 2013
Acquisition of issued and outstanding capital stock, percentage																			100.00%
Power Solutions [Member]
Business Acquisition [Line Items]
Acquisition date													Jun. 19, 2014
Acquisition of issued and outstanding capital stock, percentage																	100.00%
Emerson [Member]
Business Acquisition [Line Items]
Acquisition date													Jul. 25, 2014
Acquisition of issued and outstanding capital stock, percentage																100.00%

[1] Revised from 10-Q disclosures to reflect immaterial measurement period adjustments related to the 2014 Acquisitions. First quarter 10-Q reflected cost of sales of $114.9 million, net earnings of $5.6 million, earnings per Class A common share of $0.45 per share and earnings per Class B common share of $0.48 per share.

[2] Revised from the disclosure in the Annual Report on Form 10-K for the year ended December 31, 2014 to reflect immaterial measurement period adjustments related to the 2014 Acquisitions. The 2014 10-K reflected, for the fourth quarter of 2014, cost of sales of $120.8 million, net earnings of $2.0 million, earnings per Class A common share of $0.16 per share and earnings per Class B common share of $0.17 per share.