BUSINESS SEGMENT INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Percentage of net revenues from the DIS business	100.00%	100.00%	100.00%
Total net revenues	$ 9,872	$ 9,252	$ 9,883
Total operating income	1,346	1,262	1,428
Non-operating expenses, net	(171)	(132)	(193)
Income before income taxes and equity in earnings of equity method investees	1,175	1,130	1,235
Income tax expense	(273)	(248)	(264)
Equity in earnings of equity method investees, net of taxes	19	26	44
Depreciation and amortization	493	439	437
Total capital expenditures	$ 425	$ 408	$ 404
Total net revenues, percent	100.00%	100.00%	100.00%
Routine clinical testing and other services
Segment Reporting Information [Line Items]
Total net revenues, percent	51.00%	51.00%	44.00%
COVID-19 testing services
Segment Reporting Information [Line Items]
Total net revenues, percent	1.00%	2.00%	15.00%
Gene-based and esoteric (including advanced diagnostics) testing services
Segment Reporting Information [Line Items]
Total net revenues, percent	39.00%	38.00%	32.00%
Anatomic pathology testing services
Segment Reporting Information [Line Items]
Total net revenues, percent	6.00%	6.00%	6.00%
All other services
Segment Reporting Information [Line Items]
Total net revenues, percent	3.00%	3.00%	3.00%
DS revenues
Segment Reporting Information [Line Items]
Total net revenues, percent	3.00%	3.00%	3.00%
DIS business
Segment Reporting Information [Line Items]
Percentage of net revenues from the DIS business	97.00%	97.00%	97.00%
Total net revenues	$ 9,614	$ 8,976	$ 9,609
Less: Other segment items	(7,984)	(7,429)	(7,905)
Total operating income	1,630	1,547	1,704
Depreciation and amortization	352	319	305
Total capital expenditures	$ 410	$ 398	$ 384
Total net revenues, percent	97.00%	97.00%	97.00%
DIS business \| Physician lab services
Segment Reporting Information [Line Items]
Total net revenues, percent	68.00%	66.00%	68.00%
DIS business \| Hospital lab services
Segment Reporting Information [Line Items]
Total net revenues, percent	20.00%	21.00%	18.00%
DIS business \| Other DIS
Segment Reporting Information [Line Items]
Total net revenues, percent	9.00%	10.00%	11.00%
DS businesses
Segment Reporting Information [Line Items]
Total net revenues	$ 258	$ 276	$ 274
Total operating income	33	34	20
Depreciation and amortization	13	11	12
Total capital expenditures	7	8	19
General corporate activities
Segment Reporting Information [Line Items]
Total operating income	(317)	(319)	(296)
Depreciation and amortization	128	109	120
Total capital expenditures	$ 8	$ 2	$ 1
Minimum \| DIS business
Segment Reporting Information [Line Items]
Percentage of net revenues from the DIS business	95.00%	95.00%	95.00%

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