Segment Information - Summary of Reconciliation of Segment Operating Revenues (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	$ 138,191	$ 134,788	$ 133,974
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	135,876	132,435	131,748
Corporate and other
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	2,642	2,609	2,479
Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	$ (327)	$ (256)	$ (253)

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