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		(398)
Net shares redeemed under employee share-based compensation plans			194	(169)
Common Shares repurchased			(569)
Exercise of stock options				(33)
Share-based compensation expense and other				100
Funding of dividends declared to Retained earnings				(81)
Net income	$ 1,513				1,513
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 $81 and $(210)						898
Amounts reclassified from AOCI, net of income tax benefit of $14 and $2						(25)
Change in period, net of income tax benefit (expense) of $95 and $(208)						873
Change in period, net of income tax benefit (expense) of $7 and $(42)							78
Change in period, net of income tax benefit (expense) of $(2) and $5								(8)
Balance - end of period at Jun. 30, 2014	30,325	8,501	(630)	5,055	15,304	2,047	141	(93)	$ 2,095
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			183	(163)
Common Shares repurchased			(734)
Exercise of stock options				(29)
Share-based compensation expense and other				111
Funding of dividends declared to Retained earnings				(217)
Net income	1,623				1,623
Funding of dividends declared from Additional paid-in capital					217
Dividends declared on Common Shares					(217)
Change in period, before reclassification from AOCI, net of income tax benefit (expense) of $81 and $(210)						(294)
Amounts reclassified from AOCI, net of income tax benefit of $14 and $2						(17)
Change in period, net of income tax benefit (expense) of $95 and $(208)						(311)
Change in period, net of income tax benefit (expense) of $7 and $(42)							(278)
Change in period, net of income tax benefit (expense) of $(2) and $5								5
Balance - end of period at Jun. 30, 2015	$ 29,555	$ 7,833	$ (1,999)	$ 4,847	$ 18,267	$ 1,540	$ (859)	$ (74)	$ 607