CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]
BALANCE at Dec. 31, 2020	$ 9,359.7	$ 9.0	$ 110.3	$ 9,402.3	$ (161.9)
Net earnings attributable to Laboratory Corporation of America Holdings	769.6	0.0	0.0	769.6	0.0
Other comprehensive earnings, net of tax	(64.6)	0.0	0.0	0.0	(64.6)
Issuance of common stock under employee stock plans	(24.7)	0.0	(24.7)	0.0	0.0
Surrender of restricted stock and performance share awards	(28.1)	0.0	(28.1)	0.0	0.0
Stock compensation	28.7	0.0	28.7	0.0	0.0
Purchase of common stock	(68.5)	0.0	68.5	0.0	0.0
BALANCE at Mar. 31, 2021	10,021.5	9.0	67.1	10,171.9	(226.5)
BALANCE at Dec. 31, 2020	9,359.7	9.0	110.3	9,402.3	(161.9)
Net earnings attributable to Laboratory Corporation of America Holdings	1,237.0
Other comprehensive earnings, net of tax	(19.3)
BALANCE at Jun. 30, 2021	10,245.1	8.9	0.0	10,417.4	(181.2)
BALANCE at Mar. 31, 2021	10,021.5	9.0	67.1	10,171.9	(226.5)
Net earnings attributable to Laboratory Corporation of America Holdings	467.4	0.0	0.0	467.4	0.0
Other comprehensive earnings, net of tax	45.3	0.0	0.0	0.0	45.3
Issuance of common stock under employee stock plans	(1.9)	0.0	(1.9)	0.0	0.0
Surrender of restricted stock and performance share awards	(14.9)	0.0	(14.9)	0.0	0.0
Stock compensation	23.9	0.0	23.9	0.0	0.0
Purchase of common stock	(300.0)	0.1	78.0	221.9	0.0
BALANCE at Jun. 30, 2021	10,245.1	8.9	0.0	10,417.4	(181.2)
Retained Earnings (Accumulated Deficit)	10,456.8
BALANCE at Dec. 31, 2021	10,273.4	8.5	0.0	10,456.8	(191.9)
Net earnings attributable to Laboratory Corporation of America Holdings	491.6	0.0	0.0	491.6	0.0
Other comprehensive earnings, net of tax	(73.0)	0.0	0.0	0.0	(73.0)
Issuance of common stock under employee stock plans	(18.2)	0.0	(18.2)	0.0	0.0
Surrender of restricted stock and performance share awards	(27.3)	0.0	(27.3)	0.0	0.0
Stock compensation	38.2	0.0	38.2	0.0	0.0
BALANCE at Mar. 31, 2022	10,721.1	8.5	29.1	10,948.4	(264.9)
BALANCE at Dec. 31, 2021	10,273.4	8.5	0.0	10,456.8	(191.9)
Net earnings attributable to Laboratory Corporation of America Holdings	850.2
Other comprehensive earnings, net of tax	(313.6)
BALANCE at Jun. 30, 2022	10,400.7	8.3	0.0	10,897.9	(505.5)
BALANCE at Mar. 31, 2022	10,721.1	8.5	29.1	10,948.4	(264.9)
Net earnings attributable to Laboratory Corporation of America Holdings	358.6	0.0	0.0	358.6	0.0
Other comprehensive earnings, net of tax	(240.6)	0.0	0.0	0.0	(240.6)
Dividends, Cash	68.6
Dividends	(66.7)	0.0	0.0	(68.6)	0.0
Issuance of common stock under employee stock plans	(0.9)	0.0	(0.9)	0.0	0.0
Surrender of restricted stock and performance share awards	(10.1)	0.0	(10.1)	0.0	0.0
Stock compensation	39.4	0.0	39.4	0.0	0.0
Purchase of common stock	(400.0)	0.2	59.3	340.5	0.0
BALANCE at Jun. 30, 2022	10,400.7	$ 8.3	$ 0.0	$ 10,897.9	$ (505.5)
Retained Earnings (Accumulated Deficit)	$ 10,897.9