Business segment data - Reconciliations of Revenues and Earnings before income taxes (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Revenues	$ 93,675	$ 89,725
Investment gains (losses)	(1,605)	(6,435)
Equity method earnings	176	126
Earnings before income taxes	12,319	5,148
Operating Businesses [Member]
Segment Reporting Information [Line Items]
Revenues	92,809	88,959
Earnings before income taxes	12,367	11,615
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Investment gains (losses)	(1,605)	(6,435)
Equity method earnings	176	126
Corporate, Eliminations and Other [Member]
Segment Reporting Information [Line Items]
Revenues	866	766
Earnings before income taxes from operating businesses	$ 1,381	$ (158)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

+ References + Details

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

+ Details

- Definition

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