GOODWILL AND OTHER INTANGIBLE ASSETS - Schedule of Changes in Carrying Amount of Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, gross		$ 296,502
Accumulated impairment losses		(46,738)
Goodwill [Roll Forward]
Goodwill at December 31, 2013	249,764
Goodwill acquired during period	117,715
Foreign currency translation	170
Goodwill at March 31, 2014	367,649
U.S. Neurosurgery
Goodwill [Line Items]
Goodwill, gross		95,165
Accumulated impairment losses
Goodwill [Roll Forward]
Goodwill at December 31, 2013	95,165
Goodwill acquired during period	94,315
Foreign currency translation	88
Goodwill at March 31, 2014	189,568
U.S. Instruments
Goodwill [Line Items]
Goodwill, gross		58,033
Accumulated impairment losses
Goodwill [Roll Forward]
Goodwill at December 31, 2013	58,033
Goodwill acquired during period	0
Foreign currency translation	27
Goodwill at March 31, 2014	58,060
U.S. Extremities
Goodwill [Line Items]
Goodwill, gross		61,079
Accumulated impairment losses
Goodwill [Roll Forward]
Goodwill at December 31, 2013	61,079
Goodwill acquired during period	0
Foreign currency translation	28
Goodwill at March 31, 2014	61,107
U.S. Spine And Other
Goodwill [Line Items]
Goodwill, gross		56,325
Accumulated impairment losses		(46,738)
Goodwill [Roll Forward]
Goodwill at December 31, 2013	9,587
Goodwill acquired during period	0
Foreign currency translation	4
Goodwill at March 31, 2014	9,591
International
Goodwill [Line Items]
Goodwill, gross		25,900
Accumulated impairment losses
Goodwill [Roll Forward]
Goodwill at December 31, 2013	25,900
Goodwill acquired during period	23,400
Foreign currency translation	23
Goodwill at March 31, 2014	$ 49,323