GOODWILL AND INTANGIBLE ASSETS (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Goodwill, Balance at beginning of period			$ 5,535,848,000	$ 5,795,765,000	$ 5,795,765,000
Goodwill acquired during the period			130,192,000		28,144,000
Goodwill impairment and write-off associated with sale of business			0		(85,173,000)
Goodwill, reclassification to non-current assets held for sale			0		(218,795,000)
(Decrease) Increase related to foreign currency translation			(195,000)		15,907,000
Goodwill, Balance at end of period	5,665,845,000		5,665,845,000		5,535,848,000
Portion of goodwill associated with the clinical testing business	90.00%		90.00%		90.00%
Amortizing intangible assets, Cost	1,221,877,000		1,221,877,000		1,125,589,000
Amortizing intangible assets, Accumulated Amortization	(292,456,000)		(292,456,000)		(253,417,000)
Amortizing intangible assets, net	929,421,000		929,421,000		872,172,000
Amortization expense related to intangible assets	19,756,000	18,808,000	39,040,000	37,633,000
Remainder of 2013	40,539,000		40,539,000
Future Amortization Expense, 2014	77,376,000		77,376,000
Future Amortization Expense, 2015	65,963,000		65,963,000
Future Amortization Expense, 2016	58,922,000		58,922,000
Future Amortization Expense, 2017	55,168,000		55,168,000
Future Amortization Expense, 2018	48,428,000		48,428,000
Future Amortization Expense, Thereafter	335,546,000		335,546,000
Future Amortization Expense, Total			681,942,000
Intangible Assets Not Subject to Amortization - Tradenames [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Amortizing intangible assets, Cost	246,200,000		246,200,000		246,200,000
Amortizing intangible assets, Accumulated Amortization
Amortizing intangible assets, net	246,200,000		246,200,000		246,200,000
Intangible Assets Not Subject to Amortization - In-Process Research and Development [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Amortizing intangible assets, Cost	120,000		120,000		120,000
Amortizing intangible assets, Accumulated Amortization
Amortizing intangible assets, net	120,000		120,000		120,000
Intangible Assets Not Subject to Amortization - Other [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Amortizing intangible assets, Cost	1,159,000		1,159,000		1,159,000
Amortizing intangible assets, Accumulated Amortization
Amortizing intangible assets, net	1,159,000		1,159,000		1,159,000
Customer-related intangibles [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period	18 years
Amortizing intangible assets, Cost	657,901,000		657,901,000		566,701,000
Amortizing intangible assets, Accumulated Amortization	(190,909,000)		(190,909,000)		(173,516,000)
Amortizing intangible assets, net	466,992,000		466,992,000		393,185,000
Non-compete agreements [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period	4 years
Amortizing intangible assets, Cost	41,651,000		41,651,000		38,551,000
Amortizing intangible assets, Accumulated Amortization	(21,893,000)		(21,893,000)		(17,123,000)
Amortizing intangible assets, net	19,758,000		19,758,000		21,428,000
Technology [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period	14 years
Amortizing intangible assets, Cost	131,040,000		131,040,000		131,040,000
Amortizing intangible assets, Accumulated Amortization	(31,002,000)		(31,002,000)		(25,144,000)
Amortizing intangible assets, net	100,038,000		100,038,000		105,896,000
Other [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period	8 years
Amortizing intangible assets, Cost	143,806,000		143,806,000		141,818,000
Amortizing intangible assets, Accumulated Amortization	(48,652,000)		(48,652,000)		(37,634,000)
Amortizing intangible assets, net	95,154,000		95,154,000		104,184,000
Total Amortizing Intangible Assets [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period	16 years
Amortizing intangible assets, Cost	974,398,000		974,398,000		878,110,000
Amortizing intangible assets, Accumulated Amortization	(292,456,000)		(292,456,000)		(253,417,000)
Amortizing intangible assets, net	681,942,000		681,942,000		624,693,000
UMass, Dignity Health, ATN (Combined) [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Purchase price allocation, intangible assets	94,900,000		94,900,000
SED Medical Laboratories [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Purchase price allocation, intangible assets					19,000,000
Goodwill deductible for tax purposes					$ 28,000,000