v3.25.4

Goodwill and Other Intangibles (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning balance	$ 23,306	$ 17,231
Goodwill acquired	562	6,407
Other adjustments	469	(332)
Ending balance	24,337	23,306
Goodwill acquired	562	$ 6,407
Mc Griff Insurance Services L L C
Goodwill [Roll Forward]
Goodwill acquired	5,200
Goodwill acquired	$ 5,200

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