Note 18 - Earnings Per Share (Detail) - Computation of Basic and Diluted Earnings Per Share under the Two-class Method (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended														12 Months Ended
	Dec. 29, 2012		Sep. 29, 2012		Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2011		Oct. 01, 2011		Jul. 02, 2011	Apr. 02, 2011		Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Net income as reported	$ 12,029	[1]	$ 22,778	[2]	$ 22,963	$ 17,563	[3]	$ 15,238	[4]	$ 24,939	[5]	$ 25,269	$ 21,578	[6]	$ 75,332	$ 87,024	$ 78,663
Less: Distributed earnings available to participating securities															(30)	(16)	(3)
Less: Undistributed earnings available to participating securities															(98)	(288)	(411)
Numerator for basic earnings per share —
Undistributed and distributed earnings available to common shareholders															75,204	86,720	78,249
Add: Undistributed earnings allocated to participating securities															98	288	411
Less: Undistributed earnings reallocated to participating securities															(97)	(283)	(405)
Numerator for diluted earnings per share —
Undistributed and distributed earnings available to common shareholders															$ 75,205	$ 86,725	$ 78,255
Denominator for basic earnings per share —
Weighted-average shares (in Shares)															21,822	21,901	21,875
Effect of dilutive securities:
Common stock equivalents (in Shares)															276	354	339
Denominator for diluted earnings per share —
Adjusted for weighted-average shares & assumed conversions (in Shares)															22,098	22,255	22,214
Basic earnings per share (in Dollars per share)	$ 0.55	[1]	$ 1.04	[2]	$ 1.05	$ 0.81	[3]	$ 0.71	[4]	$ 1.13	[5]	$ 1.13	$ 0.98	[6]	$ 3.45	$ 3.96	$ 3.58
Diluted earnings per share (in Dollars per share)	$ 0.53	[1]	$ 1.03	[2]	$ 1.04	$ 0.80	[3]	$ 0.70	[4]	$ 1.12	[5]	$ 1.11	$ 0.96	[6]	$ 3.40	$ 3.90	$ 3.52

[1] In the fourth quarter of 2012, the company recorded a $7.3 million charge related to the impairment and equity method losses of Shocking Technology. (See Note 6). The company also recorded a $5.1 million charge related to a pension settlement. (See Note 13).

[2] In the third quarter of 2012, the company recorded $0.5 million charge related to the impairment of the Dnsen, Germany property. (See Note 12). 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).

[3] 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).

[4] In the fourth quarter of 2011, the company recorded $0.5 million of non-cash charges related to the step-up of inventory from the Selco A/S acquisition. (See Note 2). The company also recorded a $1.7 million decrease to income tax expense related to a deferred tax asset write-up due to an increase in the statutory rate in China.

[5] In the third quarter of 2011, the company recorded a $2.3 million charge related to asset impairments in Europe.

[6] In the first quarter of 2011, the company recorded $3.7 million of non-cash charges related to the step-up of inventory from the Cole Hersee acquisition. (See Note 2).