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- Definition

Percent of remaining performance obligations recognized as revenue in next year

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Amount billed to customers under long-term contracts or programs but not paid. Excludes amounts due that have been withheld because of retainage provisions in a contract.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions.

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The amount of expense recognized in the current period for the periodic realization of capitalized fees that were paid to salespeople, distributors, brokers, and agents at the time of the conclusion of the sale. 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 expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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Amount of revenue recognized that was previously reported as deferred or unearned revenue.

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Carrying amount of advanced commission payments.

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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 of transaction price allocated to performance obligation that has not been recognized as revenue.

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REVENUE (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Contract Receivable		$ 693.6	$ 694.4
Percent of Revenue Contributed		100.00%	100.00%
Amortization of Deferred Sales Commissions		$ 16.9	$ 14.3	$ 13.9
Accrued Sales Commission		24.2	24.0
Capitalized Contract Cost, Net		12.9	1.7
Deferred Sales Commission		37.1	25.7
Capitalized Contract Cost, Amortization		4.4	0.3	$ 0.9
Contract with Customer, Asset, Gross		396.9	318.2
Contract with Customer, Liability		354.1	$ 377.4
Deferred Revenue, Revenue Recognized		204.0
Revenue, Remaining Performance Obligation, Amount		$ 3,784.7
Percent of remaining performance obligations recognized as revenue in next year		39.00%
Contract with Customer, Performance Obligation Satisfied in Previous Period		$ 21.0
Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		9.00%	10.00%
CANADA
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		3.00%	3.00%
UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		4.00%	3.00%
SWITZERLAND
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		5.00%	5.00%
Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		3.00%	3.00%
Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		7.00%	7.00%
UNITED STATES
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		78.00%	79.00%
Covance Drug Development [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	33.50%	38.10%
Covance Drug Development [Member] \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		38.00%	33.00%
Covance Drug Development [Member] \| CANADA \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
Covance Drug Development [Member] \| UNITED KINGDOM \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		4.00%	3.00%
Covance Drug Development [Member] \| SWITZERLAND \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		5.00%	5.00%
Covance Drug Development [Member] \| Europe [Member] \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		3.00%	3.00%
Covance Drug Development [Member] \| Other countries [Member] \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		7.00%	7.00%
Covance Drug Development [Member] \| UNITED STATES \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		19.00%	15.00%
LabCorp Diagnostics [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	66.50%	62.00%	67.00%
LabCorp Diagnostics [Member] \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		27.00%	29.00%
LabCorp Diagnostics [Member] \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		8.00%	8.00%
LabCorp Diagnostics [Member] \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		18.00%	20.00%
LabCorp Diagnostics [Member] \| CANADA
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		3.00%	3.00%
LabCorp Diagnostics [Member] \| CANADA \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		2.00%	2.00%
LabCorp Diagnostics [Member] \| CANADA \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| CANADA \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| CANADA \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		1.00%	1.00%
LabCorp Diagnostics [Member] \| UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| UNITED KINGDOM \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| UNITED KINGDOM \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| UNITED KINGDOM \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| UNITED KINGDOM \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| SWITZERLAND
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| SWITZERLAND \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| SWITZERLAND \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| SWITZERLAND \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| SWITZERLAND \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Europe [Member] \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Europe [Member] \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Europe [Member] \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Europe [Member] \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Other countries [Member] \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| Other countries [Member] \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		0.00%	0.00%
LabCorp Diagnostics [Member] \| UNITED STATES
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		59.00%	64.00%
LabCorp Diagnostics [Member] \| UNITED STATES \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		25.00%	27.00%
LabCorp Diagnostics [Member] \| UNITED STATES \| Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		9.00%	10.00%
LabCorp Diagnostics [Member] \| UNITED STATES \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		8.00%	8.00%
LabCorp Diagnostics [Member] \| UNITED STATES \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		17.00%	19.00%