BUSINESS SEGMENTS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 item	Sep. 30, 2011 item
BUSINESS SEGMENTS
Number of reportable segments			3	3
Segment information
Net sales	$ 50,149	$ 54,890	$ 149,048	$ 154,630
Depreciation and amortization	2,912	3,003	8,705	8,507
Income from operations	5,150	5,666	12,936	13,059
Unallocated amounts:
Corporate expenses	(923)	(514)	(2,713)	(1,870)
Stock-based compensation	(903)	(872)	(2,838)	(2,535)
Other income (expense)	180	(9)	390	(348)
Interest expense	(216)	(326)	(622)	(1,222)
Interest income	16	1	25	4
INCOME BEFORE INCOME TAXES	5,130	5,332	12,729	11,493
Explosive Metalworking Group
Segment information
Net sales	29,771	33,396	84,680	95,221
Depreciation and amortization	1,357	1,466	4,137	4,419
Income from operations	5,451	4,599	13,138	11,758
Oilfield Products
Segment information
Net sales	18,044	18,790	57,941	51,563
Depreciation and amortization	1,417	1,399	4,181	3,709
Income from operations	1,139	1,881	4,886	3,964
AMK Welding
Segment information
Net sales	2,334	2,704	6,427	7,846
Depreciation and amortization	138	138	387	379
Income from operations	386	572	463	1,742
Total reportable segments
Segment information
Income from operations	$ 6,976	$ 7,052	$ 18,487	$ 17,464