Business segment data - Reconciliations of Revenues and Earnings before income taxes (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Revenues	$ 371,444	$ 371,433	$ 364,482
Investment gains (losses)	39,078	52,799	74,855
Equity method earnings (losses)	(9,590)	1,841	1,973
Earnings before income taxes	82,459	110,376	120,166
Operating Businesses [Member]
Segment Reporting Information [Line Items]
Revenues	368,372	370,892	364,653
Earnings before income taxes	51,714	53,936	43,637
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Investment gains (losses)	39,078	52,799	74,855
Equity method earnings (losses)	(9,590)	1,841	1,973
Corporate, Eliminations and Other [Member]
Segment Reporting Information [Line Items]
Revenues	3,072	541	(171)
Earnings before income taxes from operating businesses	$ 1,257	$ 1,800	$ (299)

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