Note 12 - Segment Information (Detail) - Segment Information (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2011
Net revenues from unaffiliated customers	$ 10,799	$ 11,681	$ 3,467	$ 35,106	$ 37,185
Intersegment sales:
Intersegment sales	1	4		11	34
Earnings (loss) before income tax expense (benefit):
Earnings (loss) before income tax expense (benefit)	1,012	2,420		2,935	6,470
Net earnings (loss):
Net earnings (loss)	664	5,182		1,955	9,094
Thermal Products [Member]
Net revenues from unaffiliated customers	6,037	7,572		18,651	19,593
Mechanical Products [Member]
Net revenues from unaffiliated customers	2,677	3,172		8,277	13,299
Electrical Products [Member]
Net revenues from unaffiliated customers	2,086	941		8,189	4,327
Intersegment Sales [Member]
Net revenues from unaffiliated customers	(1)	(4)		(11)	(34)
UNITED STATES
Net earnings (loss):
U.S.	4,123	4,797		12,052	13,820
Foreign [Member]
Net earnings (loss):
Foreign	6,676	6,884		23,054	23,365
Revenues [Member]
Net revenues from unaffiliated customers	10,799	11,681		35,106	37,185
Thermal Products [Member]
Net earnings (loss):
Net earnings (loss)	587	5,024		1,510	6,942
Mechanical Products [Member]
Net earnings (loss):
Net earnings (loss)	(213)	466		(837)	1,869
Electrical Products [Member]
Net earnings (loss):
Net earnings (loss)	247	(138)		1,409	865
Corporate [Member]
Net earnings (loss):
Net earnings (loss)	43	(170)		(127)	(582)
Mechanical Products [Member]
Intersegment sales:
Intersegment sales		3		10	7
Electrical Products [Member]
Intersegment sales:
Intersegment sales	1	1		1	27
Thermal Products [Member]
Earnings (loss) before income tax expense (benefit):
Earnings (loss) before income tax expense (benefit)	895	2,346		2,267	4,939
Mechanical Products [Member]
Earnings (loss) before income tax expense (benefit):
Earnings (loss) before income tax expense (benefit)	(324)	218		(1,256)	1,330
Electrical Products [Member]
Earnings (loss) before income tax expense (benefit):
Earnings (loss) before income tax expense (benefit)	376	(65)		2,115	615
Corporate Product [Member]
Earnings (loss) before income tax expense (benefit):
Earnings (loss) before income tax expense (benefit)	$ 65	$ (79)		$ (191)	$ (414)