Consolidated Statements of Shareholders' Equity Statement - USD ($) shares in Thousands, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Trust for Benefit of Employees [Member]
Shares, Beginning Balance at Dec. 31, 2012		1,146,493				2,850
Shareholders' equity, Beginning Balance at Dec. 31, 2012	$ 14,765.2	$ 716.6	$ 4,963.1	$ 16,088.2	$ (3,797.1)	$ (192.4)	$ (3,013.2)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income	4,684.8			4,684.8
Other comprehensive income (loss)	1,794.4				1,794.4
Cash dividends	2,102.8			2,102.8
Retirement of treasury stock, shares		(32,406)				(32,406)
Retirement of treasury stock, value	0.0	$ 20.3		1,677.8		$ 1,698.1
Purchase for treasury, shares						30,400
Purchase for treasury	(1,600.0)					$ (1,600.0)
Issuance of stock under employee stock plans-net, shares		(3,541)				(11)
Issuance of stock under employee stock plans-net, value	55.1	$ 2.2	58.0			$ 0.7
Stock-based compensation	144.9		144.9
Shareholders' equity, Ending Balance at Dec. 31, 2013	17,631.4	$ 698.5	5,050.0	16,992.4	(2,002.7)	$ (93.6)	(3,013.2)
Shares, Ending Balance at Dec. 31, 2013		1,117,628				833
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income	2,390.5			2,390.5
Other comprehensive income (loss)	(1,989.1)				(1,989.1)
Cash dividends	2,108.1			2,108.1
Retirement of treasury stock, shares		(12,579)				(12,579)
Retirement of treasury stock, value	0.0	$ 7.9		792.1		$ 800.0
Purchase for treasury, shares						12,579
Purchase for treasury	(800.0)					$ (800.0)
Issuance of stock under employee stock plans-net, shares		(6,388)				(23)
Issuance of stock under employee stock plans-net, value	92.5	$ 4.0	86.3			$ 2.2
Stock-based compensation	156.0		156.0
Shareholders' equity, Ending Balance at Dec. 31, 2014	15,373.2	$ 694.6	5,292.3	16,482.7	(3,991.8)	$ (91.4)	(3,013.2)
Shares, Ending Balance at Dec. 31, 2014		1,111,437				810
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income	2,408.4			2,408.4
Other comprehensive income (loss)	(588.9)				(588.9)
Cash dividends	2,136.0			2,136.0
Retirement of treasury stock, shares		(9,877)				(9,877)
Retirement of treasury stock, value	0.0	$ 6.2		743.3		$ 749.5
Purchase for treasury, shares						9,877
Purchase for treasury	(749.5)					$ (749.5)
Issuance of stock under employee stock plans-net, shares		(4,503)				(14)
Issuance of stock under employee stock plans-net, value	46.3	$ 2.9	42.0			$ 1.4
Stock-based compensation	217.8		217.8
Shareholders' equity, Ending Balance at Dec. 31, 2015	$ 14,571.3	$ 691.3	$ 5,552.1	$ 16,011.8	$ (4,580.7)	$ (90.0)	$ (3,013.2)
Shares, Ending Balance at Dec. 31, 2015		1,106,063				796