GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Goodwill [Roll Forward]
Beginning balance			$ 145,788
Acquired during the period			39,831
Adjustments to prior period estimates			2,007
Translation adjustment			(779)
Ending balance	186,847		186,847
Other Intangibles Assets [Roll Forward]
Balance at beginning of period			63,189
Acquired during the year			22,560
Adjustments to prior year estimates			(2,502)
Translation adjustment			(614)
Amortization	(3,434)	(3,474)	(9,221)	(8,264)
Balance at end of period	73,412		73,412
Total Goodwill and Intangible Assets [Roll Forward]
Beginning Balance			208,977
Acquired during the year			62,391
Adjustment to prior year estimates			(495)
Translation adjustment			(1,393)
Amortization	(3,434)	(3,474)	(9,221)	(8,264)
Ending Balance	260,259		260,259
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	119,883		119,883		94,888
Accumulated amortization	(46,471)		(46,471)		(31,699)
Carrying amount, net	73,412		73,412		63,189
Service Centers [Member]
Goodwill [Roll Forward]
Beginning balance					112,669
Ending balance	141,450		141,450		112,669
Innovative Pumping Solutions [Member]
Goodwill [Roll Forward]
Beginning balance					15,980
Ending balance	28,258		28,258		15,980
Supply Chain Services [Member]
Goodwill [Roll Forward]
Beginning balance					17,139
Ending balance	17,139		17,139		17,139
Vendor Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	2,496		2,496		2,496
Accumulated amortization	(1,174)		(1,174)		(1,081)
Carrying amount, net	1,322		1,322		1,415
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	114,015		114,015		90,851
Accumulated amortization	(43,035)		(43,035)		(30,010)
Carrying amount, net	70,980		70,980		60,841
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	3,372		3,372		1,541
Accumulated amortization	(2,262)		(2,262)		(608)
Carrying amount, net	1,110		1,110		933
Customer Lists [Member] | Intangible Assets Related to Jerzy Acquisition [Member]
Goodwill [Roll Forward]
Adjustments to prior period estimates			300
Customer Lists [Member] | Intangible Assets Related to HSE Acquisition [Member]
Total Goodwill and Intangible Assets [Roll Forward]
Adjustment to prior year estimates			$ 2,800