CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net earnings	$ 419.2	$ 1,280.6	$ 2,379.5
Foreign currency translation adjustments	183.1	(336.4)	(104.6)
Net benefit plan adjustments	14.6	44.8	91.7
Other comprehensive earnings (loss) before tax	197.7	(291.6)	(12.9)
Provision for income tax related to items of comprehensive earnings	(1.8)	(9.7)	(17.1)
Other comprehensive earnings (loss), net of tax	195.9	(301.3)	(30.0)
Comprehensive earnings	615.1	979.3	2,349.5
Less: Net earnings attributable to the noncontrolling interest	(1.2)	(1.5)	(2.2)
Comprehensive earnings attributable to Laboratory Corporation of America Holdings	613.9	977.8	2,347.3
Stockholders' Equity Note, Spinoff Transaction	(1,732.0)
AOCI Attributable to Parent [Member]
Other comprehensive earnings (loss), net of tax	195.9	$ (301.3)	$ (30.0)
Stockholders' Equity Note, Spinoff Transaction	238.0
Foreign Currency Translation Adjustments
Stockholders' Equity Note, Spinoff Transaction	231.6
Net Benefit Plan Adjustments
Stockholders' Equity Note, Spinoff Transaction	$ 6.4