ACQUISITIONS (Details) (USD $)	3 Months Ended		6 Months Ended				0 Months Ended				0 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Oct. 10, 2011 Kenneth Crosby [Member]	Dec. 31, 2011 C.W.Rod Tool Company [Member]	Dec. 30, 2011 C.W.Rod Tool Company [Member]	Jan. 31, 2012 Mid-Continent Safety [Member]	Feb. 29, 2012 Pump & Power Equipment, Inc. [Member]	May 02, 2012 Industrial Paramedic Services [Member]	May 01, 2012 Industrial Paramedic Services [Member]	May 01, 2012 Industrial Paramedic Services [Member] Promissory Notes [Member]
Business Acquisition [Line Items]
Purchase price						$ 16,000,000		$ 43,000,000	$ 3,800,000	$ 1,900,000		$ 24,100,000
Borrowings under existing credit facility						16,000,000		43,000,000	3,800,000	1,900,000		20,600,000
Goodwill on acquisition						5,800,000		10,000,000	1,200,000	700,000		11,900,000
Purchase price, common stock								1,100,000
Number of shares issued on acquisition (in shares)							35,714				19,685
Purchase price, cash paid								43,000,000
Cash paid in form of checks					36,700,000			36,700,000
Number of locations in which entity operates												3
Borrowings under notes													2,500,000
Stated interest rate (in hundredths)												5.00%
Purchase price allocation [Abstract]
Cash	696,000		696,000
Accounts Receivable, net	25,498,000		25,498,000
Inventory, net	15,856,000		15,856,000
Property and equipment	4,485,000		4,485,000
Goodwill and intangibles	68,793,000		68,793,000
Other assets	456,000		456,000
Assets acquired	115,784,000		115,784,000
Current liabilities assumed	(9,594,000)		(9,594,000)
Non current liabilities assumed	(5,142,000)		(5,142,000)
Net assets acquired	101,048,000		101,048,000
Pro Forma Information [Abstract]
Net sales	264,177,000	237,251,000	527,290,000	457,836,000
Net income	$ 12,139,000	$ 9,575,000	$ 24,317,000	$ 17,515,000
Per share data [Abstract]
Basic earnings (in dollars per share)	$ 0.84	$ 0.67	$ 1.69	$ 1.22
Diluted earnings (in dollars per share)	$ 0.80	$ 0.63	$ 1.60	$ 1.15