SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Advertising cost	$ 28,000,000	$ 31,000,000	$ 74,000,000
Summary of Significant Accounting Policies [Line Items]
Equity method investments carrying value	$ 123,000,000	$ 135,000,000
Percentage of net revenues	100.00%	100.00%	100.00%
Share of equity earnings from investments in affiliates	$ 19,000,000	$ 26,000,000	$ 44,000,000
Percentage of net accounts receivable	100.00%	100.00%
Goodwill, impairment loss	$ 0	$ 0
Operating income (loss)	1,346,000,000	1,262,000,000	1,428,000,000
Net income	921,000,000	908,000,000	1,015,000,000
Trading equity securities gain or (loss)	18,000,000	20,000,000	(55,000,000)
Impairment charges	0	0	$ 0
Equity Securities without readily determinable fair value	37,000,000	18,000,000
Available-for-sale debt securities	$ 0	2,000,000
Recurring Basis
Summary of Significant Accounting Policies [Line Items]
Available-for-sale debt securities		$ 2,000,000
DIS business
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues	97.00%	97.00%	97.00%
Percentage of net accounts receivable	98.00%	96.00%
Operating income (loss)	$ 1,630,000,000	$ 1,547,000,000	$ 1,704,000,000
DIS business | Government payers (principally fee-for-service)
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues	13.00%	11.00%	11.00%
Percentage of net accounts receivable	7.00%
DIS business | Patients (including coinsurance and deductible responsibilities)
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues	11.00%	12.00%	12.00%
Percentage of net accounts receivable	20.00%	20.00%
Canada
Summary of Significant Accounting Policies [Line Items]
Percentage of government revenues	2.00%
Canada | DIS business | Government payers (principally fee-for-service)
Summary of Significant Accounting Policies [Line Items]
Percentage of net accounts receivable	1.00%
Medicare and Medicaid Programs
Summary of Significant Accounting Policies [Line Items]
Percentage of net revenues	11.00%	11.00%	11.00%
Medicare and Medicaid Programs | Government payers (principally fee-for-service)
Summary of Significant Accounting Policies [Line Items]
Percentage of net accounts receivable	6.00%	7.00%
Minimum
Summary of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	5 years
Minimum | Laboratory Equipment and Furniture and Fixtures
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	5 years
Minimum | Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	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	25 years
Maximum | Building and Building Improvements
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	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
Maximum | Software and Software Development Costs
Summary of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	10 years
Substantial Ownership Interest | Minimum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	20.00%
Substantial Ownership Interest | Maximum
Summary of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	49.00%