GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Goodwill [Roll Forward]
Beginning balance	$ 188,110
Acquired during the period	185,979
Translation adjustment	0
Ending balance	374,089
Other Intangibles Assets [Roll Forward]
Balance at beginning of period	69,722
Acquired during the year	81,130
Translation adjustment	(965)
Amortization	(4,570)	(2,642)
Balance at end of period	145,317
Total Goodwill and Intangible Assets [Roll Forward]
Beginning Balance	257,832
Acquired during the year	267,109
Translation adjustment	(965)
Amortization	(4,570)	(2,642)
Ending Balance	519,406
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	194,153		114,132
Accumulated amortization	(48,836)		(44,410)
Carrying amount, net	145,317		69,722
Service Centers [Member]
Goodwill [Roll Forward]
Beginning balance			142,714
Ending balance	189,209		142,714
Innovative Pumping Solutions [Member]
Goodwill [Roll Forward]
Beginning balance			28,258
Ending balance	167,742		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	(1,237)		(1,205)
Carrying amount, net	1,259		1,291
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	189,932		109,897
Accumulated amortization	(46,769)		(42,468)
Carrying amount, net	143,163		67,429
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,725		1,739
Accumulated amortization	(830)		(737)
Carrying amount, net	$ 895		$ 1,002