Cover Page - shares shares in Millions	9 Months Ended
	Sep. 30, 2023	Oct. 27, 2023
Document Information [Table]
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		84.9
Document Fiscal Period Focus	Q3
Amendment Flag	false
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	1-11353
Entity Registrant Name	LABORATORY CORPORATION OF AMERICA HOLDINGS
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3757370
Entity Address, Address Line One	358 South Main Street
Entity Address, City or Town	Burlington,
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27215
City Area Code	336
Local Phone Number	229-1127
Title of 12(b) Security	Common Stock, $0.10 par value
Trading Symbol	LH
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Document Fiscal Year Focus	2023
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0000920148