Note 2 - Acquisition of Businesses (Details) (USD $)	3 Months Ended															12 Months Ended					1 Months Ended				3 Months Ended				12 Months Ended	0 Months Ended	1 Months Ended			3 Months Ended	0 Months Ended			3 Months Ended			12 Months Ended				1 Months Ended	0 Months Ended	12 Months Ended	1 Months Ended	0 Months Ended	12 Months Ended
	Dec. 28, 2013		Sep. 28, 2013		Jun. 29, 2013		Mar. 30, 2013		Dec. 29, 2012		Sep. 29, 2012		Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2013	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2012	Dec. 31, 2011	May 31, 2013 Hamlin, Inc. [Member] Trademarks [Member]	May 31, 2013 Hamlin, Inc. [Member] Distribution Rights [Member]	May 31, 2013 Hamlin, Inc. [Member] Patents and Licenses [Member]	May 31, 2013 Hamlin, Inc. [Member]	Dec. 28, 2013 Hamlin, Inc. [Member]	Sep. 28, 2013 Hamlin, Inc. [Member]	Sep. 30, 2013 Hamlin, Inc. [Member]	Jun. 29, 2013 Hamlin, Inc. [Member]	Dec. 28, 2013 Hamlin, Inc. [Member]	Sep. 26, 2012 Terra Power [Member]	May 31, 2012 Accel AB [Member] Trademarks [Member]	May 31, 2012 Accel AB [Member] Licensing Agreements [Member]	May 31, 2012 Accel AB [Member]	Sep. 29, 2012 Accel AB [Member]	Aug. 03, 2011 Selco A/S [Member] Trademarks [Member]	Aug. 03, 2011 Selco A/S [Member] Licensing Agreements [Member]	Aug. 03, 2011 Selco A/S [Member]	Sep. 29, 2012 Selco A/S [Member]	Mar. 31, 2012 Selco A/S [Member]	Dec. 31, 2011 Selco A/S [Member]	Dec. 31, 2013 Distribution Rights [Member]		Dec. 31, 2012 Distribution Rights [Member]		May 31, 2012 Minimum [Member] Accel AB [Member] Distribution Rights [Member]	Aug. 03, 2011 Minimum [Member] Selco A/S [Member] Distribution Rights [Member]	Dec. 28, 2013 Minimum [Member] Distribution Rights [Member]	May 31, 2012 Maximum [Member] Accel AB [Member] Distribution Rights [Member]	Aug. 03, 2011 Maximum [Member] Selco A/S [Member] Distribution Rights [Member]	Dec. 28, 2013 Maximum [Member] Distribution Rights [Member]
Note 2 - Acquisition of Businesses (Details) [Line Items]
Business Combination, Acquisition Related Costs																	$ 1,700,000	$ 900,000		$ 1,000,000					$ 200,000		$ 300,000	$ 1,200,000
Business Acquisition, Percentage of Voting Interests Acquired																								100.00%						100.00%			100.00%				100.00%
Payments to Acquire Businesses, Net of Cash Acquired																	144,382,000	34,016,000		11,077,000				144,400,000
Finite-Lived Intangible Asset, Useful Life																11 years 146 days			12 years 73 days		10 years	10 years	10 years								5 years	10 years			5 years	10 years					11 years 328 days	[1]	13 years 255 days	[1]	3 years	3 years	3 years	10 years	10 years	20 years
Business Acquisition, Inventory Step-up	1,500,000								600,000								1,500,000	600,000		3,700,000				2,100,000	1,500,000				1,500,000				400,000				700,000
Non-cash Charges Related to Inventory Step-up																										400,000	300,000	1,700,000						400,000				400,000	200,000	500,000
Non-Cash Credit Related To Inventory Stepup																									500,000
Revenue, Net	198,129,000	[2]	201,040,000	[3]	187,766,000	[4]	170,918,000	[4],[5]	158,794,000	[5],[6]	172,688,000	[6],[7]	175,853,000	160,578,000	[7],[8]	757,853,000	757,853,000	667,913,000	667,913,000	664,955,000									51,000,000
Net Income (Loss) Attributable to Parent	23,658,000	[2]	26,990,000	[3]	26,648,000	[4]	11,488,000	[4],[5]	12,029,000	[5],[6]	22,778,000	[6],[7]	22,963,000	17,563,000	[7],[8]		88,784,000	75,332,000		87,024,000									1,200,000
Business Combination, Consideration Transferred																														10,600,000							11,100,000
Payments to Acquire Businesses, Gross																																	23,900,000
Cost of Goods Sold																																							$ 200,000

[1] Increase to gross carrying value for in 2013 is related to the preliminary Hamlin acquisition purchase price allocation discussed in Note 2. Other changes are primarily due to the impact of foreign currency translation adjustments.

[2] In the fourth quarter of 2013, the company recorded a $2.8 million charge to income tax expense related to the company's impairment of its investment in Shocking Technologies in the fourth quarter of 2012. (See Note 6). The company also recorded a $0.5 million non-cash credit related to the step-up of inventory from the Hamlin acquisition (See Note 2) and $0.2 million in acquisition expenses for the Hamlin acquisition.

[3] In the third quarter of 2013, the company recorded a $0.3 million non-cash charge related to the step-up of inventory from the Hamlin acquisition (See Note 2). The company also recorded $0.3 million in acquisition charges related to the Hamlin acquisition.

[4] In the second quarter of 2013, the company recorded a $1.7 million non-cash charge related to step-up of inventory from the Hamlin acquisition (See Note 2). The company also recorded $1.2 million in acquisition charges related to the Hamlin acquisition.

[5] In the first quarter of 2013, the company recorded a $10.7 million charge related to the impairment of Shocking Technologies. Additionally, the company restated net income for a $3.3 million charge to income tax expense related to the company's investment in Shocking Technologies (See Note 6).

[6] In the fourth quarter of 2012, the company recorded a $7.3 million charge related to the impairment and equity method losses of Shocking Technologies. (See Note 6). The company also recorded a $5.1 million charge related to a pension settlement (See Note 12).

[7] In the third quarter of 2012, the company recorded $0.5 million charge related to the impairment of the Dnsen, Germany property (See Note 11). The company also recorded $0.6 million in acquisition charges related to the Accel and Terra Power acquisitions and $0.4 million of non-cash charges related to the step-up of inventory from the Accel acquisition (See Note 2).

[8] In the first quarter of 2012, the company recorded a $0.2 million non-cash charge related to the step-up of inventory from the Selco acquisition (See Note 2).