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FAIR VALUE MEASUREMENTS (Narrative) (Details)	3 Months Ended
FAIR VALUE MEASUREMENTS (Narrative) (Details)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jul. 01, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of debt	$ 4,600,000,000	$ 4,600,000,000
UMass Joint Venture
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Ownership percentage by noncontrolling owners				18.90%
Fair Value, Inputs, Level 3 \| Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total fair value adjustments included in earnings - realized/unrealized	3,000,000
Liability	113,000,000	104,000,000
Fair Value, Inputs, Level 3 \| Contingent Consideration \| Other Liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liability	79,000,000	99,000,000
Fair Value, Inputs, Level 3 \| Contingent Consideration \| Accounts Payable and Accrued Expenses
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liability	$ 34,000,000	$ 5,000,000
Haystack Oncology, Inc. \| Comparable Company Revenue Volatility
Business Acquisition [Line Items]
Measurement input	0.40
Haystack Oncology, Inc. \| Discount rate
Business Acquisition [Line Items]
Measurement input	0.105
Haystack Oncology, Inc. \| Additional, Based on Revenue
Business Acquisition [Line Items]
Maximum contingent consideration payment			$ 100,000,000
Haystack Oncology, Inc. \| Additional, Reimbursement Coverage
Business Acquisition [Line Items]
Maximum contingent consideration payment			$ 50,000,000
Haystack Oncology, Inc. \| Additional Impact \| Discount rate
Business Acquisition [Line Items]
Measurement input	0.05
Haystack Oncology, Inc. \| Changing Comparable Company Revenue Volatility \| Comparable Company Revenue Volatility
Business Acquisition [Line Items]
Measurement input	0.30
Increase in contingent consideration liability	$ 8,000,000
Haystack Oncology, Inc. \| Changing Discount Rate \| Comparable Company Revenue Volatility
Business Acquisition [Line Items]
Increase in contingent consideration liability	$ 5,000,000
Haystack Oncology, Inc. \| Changing Discount Rate \| Discount rate
Business Acquisition [Line Items]
Measurement input	0.070