Fair Value Measurements - Schedule of Reconciliation for Assets and Liabilities Measured at Fair Value (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026 USD ($)	Sep. 30, 2026 USD ($)
Investment in Unconsolidated Subsidiaries
Investment in Unconsolidated Subsidiaries
Beginning balance	$ 19	$ 19
Net change in fair value	0	0
Sales / Payments	0	0
Ending balance	19	19
Contingent Consideration
Contingent Consideration
Beginning balance	34	65
Net change in fair value	(4)	(23)
Sales / Payments	(6)	(18)
Ending balance	$ 24	$ 24
Contingent Consideration \| Volatility \| Monte Carlo Pricing Model
Contingent Consideration
Alternative investment, measurement input percentage	0.176	0.176
Contingent Consideration \| Discount Rate \| Monte Carlo Pricing Model
Contingent Consideration
Alternative investment, measurement input percentage	0.049	0.049

Value of input used to measure alternative investment.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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