CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Millions	Total	Common Stock [Member]	Paid-In-Surplus [Member]	Retained Earnings [Member]	Unrealized Appreciation of Investments Including Unrealized Other-Than-Temporary Impairment Losses [Member]	Foreign Currency Translation Gains [Member]	Postretirement Benefit Costs Not Yet Recognized in Net Income [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock, at Cost [Member]
Balance, Beginning of Year at Dec. 31, 2011		$ 372	$ 190	$ 18,903	$ 1,736	$ 146	$ (687)		$ (5,359)
Net Income	1,443			1,443
Repurchase of Shares									(907)
Changes Related to Stock-Based Employee Compensation (includes tax benefit of $28 and $24)			(28)
Change During Period, Net of Tax	375				352	(17)	40
Dividends Declared (per share $1.32 and $1.23)				(331)
Shares Issued Under Stock-Based Employee Compensation Plans									121
Balance, End of Period at Sep. 30, 2012	15,974	372	162	20,015	2,088	129	(647)	1,570	(6,145)
Balance, Beginning of Year at Dec. 31, 2012	15,827	372	178	20,009	2,013	135	(717)		(6,163)
Net Income	1,776			1,776
Repurchase of Shares									(975)
Changes Related to Stock-Based Employee Compensation (includes tax benefit of $28 and $24)			(28)
Change During Period, Net of Tax	(716)				(699)	(63)	46
Dividends Declared (per share $1.32 and $1.23)				(342)
Shares Issued Under Stock-Based Employee Compensation Plans									79
Balance, End of Period at Sep. 30, 2013	$ 15,621	$ 372	$ 150	$ 21,443	$ 1,314	$ 72	$ (671)	$ 715	$ (7,059)