Revenue from External Customers by Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenue from External Customers [Line Items]
Revenue	$ 3,408	$ 3,513	$ 6,877	$ 6,840
UNITED STATES
Revenue from External Customers [Line Items]
Revenue	1,627	1,600	3,196	3,145
GERMANY
Revenue from External Customers [Line Items]
Revenue	345	467	826	893
UNITED KINGDOM
Revenue from External Customers [Line Items]
Revenue	399	418	826	835
Other countries
Revenue from External Customers [Line Items]
Revenue	$ 1,037	$ 1,028	$ 2,029	$ 1,967

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