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FAIR VALUE MEASUREMENTS - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Jun. 20, 2023 USD ($)	Jul. 01, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of debt	$ 5,600,000,000		$ 5,600,000,000		$ 5,700,000,000
Invigorate Program
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restructuring and impairment charges	2,000,000	$ 25,000,000	9,000,000	$ 36,000,000
Income Statement Location [Axis]: us-gaap:CostOfRevenue \| Invigorate Program
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restructuring and impairment charges				6,000,000
Income Statement Location [Axis]: us-gaap:OtherOperatingIncomeExpenseNet \| Invigorate Program
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restructuring and impairment charges		24,000,000		24,000,000
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense \| Invigorate Program
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restructuring and impairment charges		$ 1,000,000		$ 6,000,000
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			4,000,000
Liability	100,000,000		100,000,000		96,000,000
Fair Value, Inputs, Level 3 \| Contingent Consideration \| Balance Sheet Location [Axis]: us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liability	51,000,000		51,000,000		51,000,000
Fair Value, Inputs, Level 3 \| Contingent Consideration \| Balance Sheet Location [Axis]: us-gaap:OtherLiabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liability	$ 49,000,000		$ 49,000,000		$ 45,000,000
Haystack Oncology, Inc. \| Comparable Company Revenue Volatility
Business Combination [Line Items]
Measurement input	0.25		0.25
Haystack Oncology, Inc. \| Discount rate
Business Combination [Line Items]
Measurement input	0.070		0.070
Haystack Oncology, Inc. \| Additional, Based on Revenue
Business Combination [Line Items]
Maximum contingent consideration payment						$ 100,000,000
Haystack Oncology, Inc. \| Additional, Reimbursement Coverage
Business Combination [Line Items]
Maximum contingent consideration payment						$ 50,000,000
Haystack Oncology, Inc. \| Additional Impact \| Discount rate
Business Combination [Line Items]
Measurement input	0.05		0.05
Haystack Oncology, Inc. \| Changing Comparable Company Revenue Volatility \| Comparable Company Revenue Volatility
Business Combination [Line Items]
Measurement input	0.30		0.30
Increase in contingent consideration liability	$ 3,000,000
Haystack Oncology, Inc. \| Changing Discount Rate \| Comparable Company Revenue Volatility
Business Combination [Line Items]
Increase in contingent consideration liability	$ 4,000,000
Haystack Oncology, Inc. \| Changing Discount Rate \| Discount rate
Business Combination [Line Items]
Measurement input	0.105		0.105