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v3.25.3

FAIR VALUE - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fair value measurement, transfers into or out of level 3 |  |  |  | $ 0 | $ 0 |
Swap asset |  |  |  | 82,000,000 |  |
Swap liability |  | $ 129,000,000 |  | 34,000,000 |  | $ 129,000,000
Impairment of indefinite-lived intangible assets | $ 32,000,000 | 200,000,000 | $ 0 | 32,000,000 | $ 0 |
WCAS, Cohort Of Clinics | Minimum |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Call option strike price |  |  |  | 3,000,000,000 |  |
WCAS, Cohort Of Clinics | Maximum |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Call option strike price |  |  |  | 5,000,000,000 |  |
Put Option |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fair value of financial liability |  | 883,000,000 |  | 1,350,000,000 |  | 883,000,000
Call Option |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fair value of financial asset |  | 10,000,000 |  | 13,000,000 |  | 10,000,000
Commercial Paper |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Commercial paper borrowings |  | 0 |  | 0 |  | 0
Carrying Value |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Debt outstanding |  | 11,700,000,000 |  | 12,600,000,000 |  | 11,700,000,000
Fair Value |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Debt outstanding |  | 11,200,000,000 |  | 12,300,000,000 |  | 11,200,000,000
Interest Rate Swap |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cumulative, aggregate adjustment to the carrying value of senior note |  |  |  | 48,000,000 |  |
Recurring Basis |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Assets, fair value |  | 21,101,000,000 |  | $ 23,000,000,000 |  | $ 21,101,000,000
Unobservable Inputs (Level 3) | Investments | Fair Value Risk |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Concentration risk (as percent) |  |  |  | 1.80% |  | 1.50%
Unobservable Inputs (Level 3) | Recurring Basis |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Assets, fair value |  | $ 322,000,000 |  | $ 410,000,000 |  | $ 322,000,000

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