Segment Information - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) segment	Mar. 31, 2025 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segment \| segment	2
Total revenue	$ 5,034	$ 4,729
Eliminations
Segment Reporting Information [Line Items]
Total revenue	(7)	(7)
Eliminations \| Risk Capital
Segment Reporting Information [Line Items]
Total revenue	4	5
Eliminations \| Human Capital
Segment Reporting Information [Line Items]
Total revenue	$ 3	$ 2

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details