Consolidated Statements Of Operations and Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues
Net premiums written	$ 7,573	$ 4,709	$ 21,207	$ 13,569
Decrease (increase) in unearned premiums	115	10	483	(563)
Net premiums earned	7,688	4,719	21,690	13,006
Net investment income	739	549	2,121	1,662
Net Realized Gains Losses [Abstract]
Other-than-temporary impairment (OTTI) losses gross	(12)	(35)	(99)	(62)
Portion of OTTI losses recognized in other comprehensive income (OCI)	0	5	8	11
Net OTTI losses recognized in income	(12)	(30)	(91)	(51)
Net realized gains (losses) excluding OTTI losses	112	(367)	(419)	(309)
Total net realized gains (losses) (includes $33, $(49), $(117), and $(18) reclassified from AOCI)	100	(397)	(510)	(360)
Total revenues	8,527	4,871	23,301	14,308
Expenses
Losses and loss expenses	4,269	2,643	12,197	7,182
Policy benefits	155	89	427	384
Policy acquisition costs	1,514	771	4,487	2,205
Administrative expenses	772	568	2,373	1,700
Interest expense	152	68	451	207
Other (income) expense	(91)	12	(92)	(61)
Amortization of purchased intangibles	4	51	16	136
Chubb integration expenses	115	9	361	9
Total expenses	6,890	4,211	20,220	11,762
Income before income tax	1,637	660	3,081	2,546
Income tax expense (includes $11, $(4), $16 and $10 on reclassified unrealized gains and losses)	277	132	556	395
Net income	1,360	528	2,525	2,151
Other comprehensive income (loss)
Unrealized appreciation (depreciation)	247	(321)	2,099	(696)
Reclassification adjustment for net realized (gains) losses included in net income	(33)	49	117	18
Unrealized appreciation (Depreciation) after reclassification adjustment	214	(272)	2,216	(678)
Change in:
Cumulative translation adjustment	(124)	(575)	269	(860)
Pension liability	5	3	8	10
Other comprehensive income (loss), before income tax	95	(844)	2,493	(1,528)
Income tax (expense) benefit related to OCI items	(79)	45	(561)	145
Other comprehensive income (loss)	16	(799)	1,932	(1,383)
Comprehensive income (loss)	$ 1,376	$ (271)	$ 4,457	$ 768
Earnings per share
Basic earnings per share	$ 2.90	$ 1.63	$ 5.48	$ 6.60
Diluted earnings per share	$ 2.88	$ 1.62	$ 5.44	$ 6.53
The Chubb Corporation [Member]
Expenses
Chubb integration expenses		$ 9