Business segment data - Reconciliations of Revenues and Earnings before income taxes (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Revenues	$ 101,808	$ 92,515	$ 195,483	$ 182,240
Investment gains (losses)	16,077	6,364	14,472	(71)
Equity method earnings	248	(4,745)	424	(4,619)
Earnings before income taxes	32,063	14,750	44,382	19,898
Operating Businesses [Member]
Segment Reporting [Line Items]
Revenues	101,014	91,802	193,823	180,761
Earnings before income taxes	14,376	13,378	26,743	24,993
Segment Reconciling Items [Member]
Segment Reporting [Line Items]
Investment gains (losses)	16,077	6,364	14,472	(71)
Equity method earnings	248	(4,745)	424	(4,619)
Corporate, Eliminations and Other [Member]
Segment Reporting [Line Items]
Revenues	794	713	1,660	1,479
Earnings before income taxes from operating businesses	$ 1,362	$ (247)	$ 2,743	$ (405)

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

- 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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