COMMITMENTS AND CONTINGENCIES (Details) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2011 USD ($)	Jun. 30, 2011 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($)	Mar. 31, 2016 USD ($)	Feb. 19, 2015 USD ($)	Aug. 24, 2012 Recipients $ / Violation
Loss Contingencies [Line Items]
Litigation settlement expense in connection with the California False Claims Act lawsuit		$ 34.5
Previously Recorded Litigation Reserve In Connection With False Claims Act Lawsuit		$ 15.0
Litigation Settlement, Gross	$ 49.5
Payment reduction by Assembly Bill No. 97				10.00%
Percent of lowest maximum (cap on payments)				80.00%
Loss Contingency, Damages Awarded, Value					$ 50.0
Loss Contingency Damages Awarded Gross			$ 20.8	$ 0.2
Number of Recipients | Recipients								39
Proposed damages per violation | $ / Violation								0.0005
Loss Contingency Damages Awarded Net			$ 15.8
Reduction for Plaintiff Negligence			25.00%
Company's apportioned responsibility					50.00%
Co-defendant's apportioned responsibility					50.00%
Loss contingency reduced damages awarded gross			$ 5.0
Loss contingency reduced damages awarded net			$ 4.4
Purchase Price Per Share | $ / shares				$ 5.25
Amount Outstanding Letters Of Credit						$ 55.0
Covance [Member]
Loss Contingencies [Line Items]
Total acquisition consideration (cash and non-cash)							$ 6,150.7
Tri-State Clinical Laboratory Services, LLC [Member]
Loss Contingencies [Line Items]
Ownership interest percentage, parent		50.00%