SUMMARY OF SIGNIFICANT ACCOUNTING - NET SALES - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Percent of Revenue Contributed	100.00%	100.00%	100.00%
Intercompany revenue elimination	$ 152.6
Revenues	$ 13,978.5	$ 11,554.8	$ 11,333.4
LabCorp Diagnostics [Member]
Percent of Revenue Contributed	65.00%	60.00%	62.00%
Covance Drug Development [Member]
Percent of Revenue Contributed	35.00%	40.00%

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details