GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 5,705.1		$ 5,423.6
Goodwill	8,165.8		7,958.9
Amortization of intangibles and other assets	67.1	$ 92.1
Adjustments to goodwill	(79.3)
Estimated amortization expense, 2012	191.7
Estimated amortization expense, 2013	259.9
Estimated amortization expense, 2014	255.3
Estimated amortization expense, 2015	243.1
Estimated amortization expense, 2016	233.3
Estimated amortization expense, Thereafter	2,707.0
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	(0.4)
Amortization of intangible assets	67.1	$ 92.1
LabCorp Diagnostics [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	4,141.5		4,046.2
Adjustments to goodwill	(47.8)
Covance Drug Development [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	4,024.3		$ 3,912.7
Adjustments to goodwill	$ (31.5)

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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