Revenue from External Customers by Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Revenue from External Customers [Line Items]
Revenue	$ 3,319	$ 3,499	$ 10,196	$ 10,339
UNITED STATES
Revenue from External Customers [Line Items]
Revenue	1,569	1,583	4,765	4,728
GERMANY
Revenue from External Customers [Line Items]
Revenue	378	474	1,204	1,367
UNITED KINGDOM
Revenue from External Customers [Line Items]
Revenue	396	432	1,222	1,267
Other countries
Revenue from External Customers [Line Items]
Revenue	$ 976	$ 1,010	$ 3,005	$ 2,977

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details