Schedule II Schedule II (STATEMENTS OF OPERATIONS - Parent Company Only) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Condensed Financial Statements, Captions [Line Items]
Equity in net income of subsidiaries and affiliates		$ 967	$ 867	$ 1
Total revenues		55,753	49,735	43,097
Administrative and other (income) expense		4,380	4,007	3,395
Integration expenses		39	69	48
Income Tax Expense (Benefit)		(1,815)	(511)	(1,239)
Total expenses		44,298	40,209	36,612
Net income attributable to Chubb		9,272	9,028	5,246
Comprehensive income (loss) attributable to Chubb		7,437	12,404	(3,865)
Chubb limited (Parent Guarantor)
Condensed Financial Statements, Captions [Line Items]
Investment income (loss)	[1]	(24)	(21)	83
Equity in net income of subsidiaries and affiliates		9,385	9,065	5,256
Total revenues		9,361	9,044	5,339
Administrative and other (income) expense		74	72	65
Integration expenses		0	0	10
Income Tax Expense (Benefit)		(15)	56	(18)
Total expenses		89	16	93
Net income attributable to Chubb		9,272	9,028	5,246
Comprehensive income (loss) attributable to Chubb		$ 7,437	$ 12,404	$ (3,865)

[1] Includes net investment income, interest income, and net realized gains (losses).