Consolidated Statements Of Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Net Unrealized Investment Gain (Loss) [Member]	Accumulated Translation Adjustment [Member]	Accumulated Defined Benefit Plans Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance - beginning of period at Dec. 31, 2013		$ 8,899	$ (255)	$ 5,238	$ 13,791	$ 1,174	$ 63	$ (85)
Dividends declared on Common Shares – par value reduction		(621)
Net shares redeemed under employee share-based compensation plans			217	(167)
Common Shares repurchased			(1,019)
Exercise of stock options				(44)
Share-based compensation expense and other				153
Funding of dividends declared to Retained earnings				(81)
Net income	$ 2,298				2,298
Funding of dividends declared from Additional paid-in capital					81
Dividends declared on Common Shares					(81)
Change in period, before reclassification from AOCI, net of income tax benefit (expense) of $102 and $(168)						565
Amounts reclassified from AOCI, net of income tax benefit of $10 and $7						18
Change in period, net of income tax benefit (expense) of $112 and $(161)						583
Change in period, net of income tax benefit (expense) of $35 and $7							(124)
Change in period, net of income tax benefit (expense) of $(2) and $3								(3)
Balance - end of period at Sep. 30, 2014	30,017	8,278	(1,057)	5,099	16,089	1,757	(61)	(88)	$ 1,608
Balance - beginning of period at Dec. 31, 2014	29,587	8,055	(1,448)	5,145	16,644	1,851	(581)	(79)
Dividends declared on Common Shares – par value reduction		(222)
Net shares redeemed under employee share-based compensation plans			208	(157)
Common Shares repurchased			(734)
Exercise of stock options				(43)
Share-based compensation expense and other				155
Funding of dividends declared to Retained earnings				(435)
Net income	2,151				2,151
Funding of dividends declared from Additional paid-in capital					435
Dividends declared on Common Shares					(435)
Change in period, before reclassification from AOCI, net of income tax benefit (expense) of $102 and $(168)						(594)
Amounts reclassified from AOCI, net of income tax benefit of $10 and $7						28
Change in period, net of income tax benefit (expense) of $112 and $(161)						(566)
Change in period, net of income tax benefit (expense) of $35 and $7							(825)
Change in period, net of income tax benefit (expense) of $(2) and $3								8
Balance - end of period at Sep. 30, 2015	$ 29,127	$ 7,833	$ (1,974)	$ 4,665	$ 18,795	$ 1,285	$ (1,406)	$ (71)	$ (192)