GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Goodwill [Roll Forward]
Beginning balance	$ 188,110
Acquired during the period	185,609
Translation adjustment	0
Ending balance	373,719
Other Intangibles Assets [Roll Forward]
Balance at beginning of period	69,722
Acquired during the year	85,264
Translation adjustment	(1,158)
Amortization	(13,874)	(9,221)
Balance at end of period	139,954
Total Goodwill and Intangible Assets [Roll Forward]
Beginning Balance	257,832
Acquired during the year	270,873
Translation adjustment	(1,158)
Amortization	(13,874)	(9,221)
Ending Balance	513,673
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	198,029		114,132
Accumulated amortization	(58,075)		(44,410)
Carrying amount, net	139,954		69,722
Service Centers [Member]
Goodwill [Roll Forward]
Beginning balance			142,714
Ending balance	192,482		142,714
Innovative Pumping Solutions [Member]
Goodwill [Roll Forward]
Beginning balance			28,258
Ending balance	164,099		28,258
Supply Chain Services [Member]
Goodwill [Roll Forward]
Beginning balance			17,138
Ending balance	17,138		17,138
Vendor Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	2,496		2,496
Accumulated amortization	(1,299)		(1,205)
Carrying amount, net	1,197		1,291
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	193,794		109,897
Accumulated amortization	(55,738)		(42,468)
Carrying amount, net	138,056		67,429
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,739		1,739
Accumulated amortization	(1,038)		(737)
Carrying amount, net	$ 701		$ 1,002