SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Advertising cost		$ 31,000,000	$ 74,000,000	$ 78,000,000
Summary of Significant Accounting Policies [Line Items]
Equity method investments carrying value	$ 135,000,000	$ 135,000,000	$ 132,000,000
Percentage of net revenues		100.00%	100.00%	100.00%
Share of equity earnings from investments in affiliates		$ 26,000,000	$ 44,000,000	$ 78,000,000
Percentage of net accounts receivable	100.00%	100.00%	100.00%
Goodwill, impairment loss		$ 0	$ 0
Operating income (loss)		1,262,000,000	1,428,000,000	2,381,000,000
Net income		908,000,000	1,015,000,000	2,080,000,000
Trading equity securities gain or (loss)		20,000,000	(55,000,000)	56,000,000
Impairment charges		0	0	$ 0
Equity Securities without readily determinable fair value	$ 18,000,000	18,000,000	4,000,000
Available-for-sale debt securities	2,000,000	2,000,000	2,000,000
Recurring Basis
Summary of Significant Accounting Policies [Line Items]
Available-for-sale debt securities	2,000,000	$ 2,000,000	$ 2,000,000
Facility-Related Costs
Summary of Significant Accounting Policies [Line Items]
Impairment charges	$ 29,000,000
DIS business
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues		97.00%	97.00%	97.00%
Percentage of net accounts receivable	96.00%	96.00%	96.00%
Operating income (loss)		$ 1,547,000,000	$ 1,704,000,000	$ 2,646,000,000
DIS business | Government payers
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues		11.00%	11.00%	10.00%
Percentage of net accounts receivable	7.00%	7.00%	6.00%
DIS business | Patients (including coinsurance and deductible responsibilities)
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues		12.00%	12.00%	12.00%
Percentage of net accounts receivable	20.00%	20.00%	18.00%
Minimum
Summary of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	5 years	5 years
Minimum | Laboratory Equipment and Furniture and Fixtures
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	5 years	5 years
Minimum | Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	5 years	5 years
Minimum | DIS business
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues		95.00%	95.00%	95.00%
Maximum
Summary of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	20 years	20 years
Maximum | Building and Building Improvements
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	31 years 6 months	31 years 6 months
Maximum | Laboratory Equipment and Furniture and Fixtures
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	12 years	12 years
Maximum | Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	10 years	10 years
Substantial Ownership Interest | Minimum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	20.00%	20.00%
Substantial Ownership Interest | Maximum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	49.00%	49.00%