Segment Information - Schedule of Inter-Segment Revenue (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Segment Reporting [Line Items]
Revenue	$ (4,101)	$ (3,997)	$ (13,381)	$ (12,881)
Eliminations
Segment Reporting [Line Items]
Revenue	2	3	13	12
Eliminations \| Risk Capital
Segment Reporting [Line Items]
Revenue	0	0	5	5
Eliminations \| Human Capital
Segment Reporting [Line Items]
Revenue	$ 2	$ 3	$ 8	$ 7

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details