Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Net income	$ 9,015	$ 5,246	$ 8,525
Net loss attributable to noncontrolling interests	(13)	0	0
Net income attributable to Chubb	$ 9,028	$ 5,246	$ 8,525
Weighted-average shares outstanding	410,845,263	419,779,847	439,968,422
Share-based compensation plans	3,357,305	3,747,597	3,228,856
Adjusted weighted-average shares outstanding and assumed conversions	414,202,568	423,527,444	443,197,278
Basic earnings per share attributable to Chubb	$ 21.97	$ 12.50	$ 19.38
Diluted earnings per share attributable to Chubb	$ 21.80	$ 12.39	$ 19.24
Potential anti-dilutive share conversions	2,385,099	1,467,840	1,532,066