Consolidated Statements Of Shareholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock, Common	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Parent	Noncontrolling Interest
Total shareholders' equity		$ 241	$ (4,400)	$ 15,665	$ 54,810	$ (6,809)		$ 4,184
Treasury Stock, Retired, Cost Method, Amount		(6)	(2,527)		(2,521)
Common Shares repurchased			(886)
Net shares issued under employee share-based compensation plans			278
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures				(142)
Exercise of stock options				(19)
Share-based compensation expense				172
Adjustments to Additional Paid in Capital, Other				(31)
Funding of dividends declared to Retained earnings				(719)
Net income attributable to Chubb	$ 4,373				4,373
Funding of dividends declared from Additional paid-in capital					719
Dividends declared on Common Shares					(719)
Other Comprehensive Income (Loss), Net of Tax	(1,566)					(1,495)
Net increase (decrease) due to consolidation, deconsolidation, and other transactions								(707)
Net income (loss) attributable to noncontrolling interests	137							137
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest								(71)
Other								(6)
Total shareholders' equity		241	(4,461)	15,188	56,953	(7,386)		3,896
Treasury Stock, Retired, Cost Method, Amount		(6)	(2,527)		(2,521)
Common Shares repurchased			(570)
Net shares issued under employee share-based compensation plans			(23)
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures				17
Exercise of stock options				0
Share-based compensation expense				90
Adjustments to Additional Paid in Capital, Other				0
Funding of dividends declared to Retained earnings				(369)
Net income attributable to Chubb	2,230				2,230
Funding of dividends declared from Additional paid-in capital					369
Dividends declared on Common Shares					(369)
Other Comprehensive Income (Loss), Net of Tax	(961)					(918)
Net increase (decrease) due to consolidation, deconsolidation, and other transactions								(296)
Net income (loss) attributable to noncontrolling interests	(14)							(14)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest								(43)
Other								(6)
Total shareholders' equity	64,575	235	(2,481)	14,926	56,662	(8,304)	$ 61,038	3,537
Total shareholders' equity	68,394	235	(3,524)	14,393	61,561	(8,644)		4,373
Treasury Stock, Retired, Cost Method, Amount		(4)	(1,942)		(1,939)
Common Shares repurchased			(1,061)
Net shares issued under employee share-based compensation plans			181
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures				(120)
Exercise of stock options				2
Share-based compensation expense				189
Adjustments to Additional Paid in Capital, Other				53
Funding of dividends declared to Retained earnings				(754)
Net income attributable to Chubb	4,299				4,299
Funding of dividends declared from Additional paid-in capital					754
Dividends declared on Common Shares					(754)
Other Comprehensive Income (Loss), Net of Tax	2,598					2,586
Net increase (decrease) due to consolidation, deconsolidation, and other transactions								624
Net income (loss) attributable to noncontrolling interests	43							43
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest								12
Other								0
Total shareholders' equity		231	(1,799)	13,976	60,953	(7,635)		5,029
Treasury Stock, Retired, Cost Method, Amount		0	0		0
Common Shares repurchased			(676)
Net shares issued under employee share-based compensation plans			(13)
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures				26
Exercise of stock options				1
Share-based compensation expense				95
Adjustments to Additional Paid in Capital, Other				53
Funding of dividends declared to Retained earnings				(388)
Net income attributable to Chubb	2,968				2,968
Funding of dividends declared from Additional paid-in capital					388
Dividends declared on Common Shares					(388)
Other Comprehensive Income (Loss), Net of Tax	1,594					1,577
Net increase (decrease) due to consolidation, deconsolidation, and other transactions								(25)
Net income (loss) attributable to noncontrolling interests	31							31
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest								17
Other								0
Total shareholders' equity	$ 74,447	$ 231	$ (2,462)	$ 13,763	$ 63,921	$ (6,058)	$ 69,395	$ 5,052