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]	Postretirement Benefit Costs Not Yet Recognized in Net Income [Member]	Foreign Currency Translation Gains [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock, at Cost [Member]
Balance, Beginning of Year at Dec. 31, 2012		$ 372	$ 178	$ 20,009	$ 2,013	$ (717)	$ 135		$ (6,163)
Net Income	656			656
Repurchase of Shares									(326)
Changes Related to Stock-Based Employee Compensation (includes tax benefit of $14 and $27)			(73)
Change During Period, Net of Tax	(29)				4	17	(50)
Dividends Declared (per share $.50 and $.44)				(115)
Shares Issued Under Stock-Based Employee Compensation Plans									76
Balance, End of Period at Mar. 31, 2013	16,016	372	105	20,550	2,017	(700)	85	1,402	(6,413)
Balance, Beginning of Year at Dec. 31, 2013	16,097	372	171	21,902	1,225	(253)	63		(7,383)
Net Income	449			449
Repurchase of Shares									(409)
Changes Related to Stock-Based Employee Compensation (includes tax benefit of $14 and $27)			(63)
Change During Period, Net of Tax	222				235	6	(19)
Dividends Declared (per share $.50 and $.44)				(124)
Shares Issued Under Stock-Based Employee Compensation Plans									54
Balance, End of Period at Mar. 31, 2014	$ 16,226	$ 372	$ 108	$ 22,227	$ 1,460	$ (247)	$ 44	$ 1,257	$ (7,738)