CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balances at beginning of period at Dec. 31, 2012	$ 5,694.5	$ 8.8	$ (4,823.2)	$ 7,536.0	$ 3,022.6	$ (49.7)
Increase (decrease) in stockholders' equity
Net income	1,449.9				1,449.9
Other comprehensive income	143.7					143.7
Exercise of stock options and conversion of restricted stock units	554.0	0.2	(69.7)	623.5
Shares purchased under share repurchase program	(2,769.2)		(2,769.2)
Issuance of common stock for employee benefit plans	22.0	0.1		21.9
Expense related to share-based compensation	325.0			325.0
Income tax benefit upon exercise of stock options	170.0			170.0
Balances at end of period at Dec. 31, 2013	5,589.9	9.1	(7,662.1)	8,676.4	4,472.5	94.0
Increase (decrease) in stockholders' equity
Net income	1,999.9				1,999.9
Other comprehensive income	820.8					820.8
Exercise of stock options and conversion of restricted stock units	298.2	0.1	(126.1)	424.2
Shares purchased under share repurchase program	(2,929.5)		(2,929.5)
Issuance of common stock for employee benefit plans	45.4		18.9	26.5
Expense related to share-based compensation	447.5			447.5
Income tax benefit upon exercise of stock options	252.6			252.6
Balances at end of period at Dec. 31, 2014	6,524.8	9.2	(10,698.8)	9,827.2	6,472.4	914.8
Increase (decrease) in stockholders' equity
Net income	1,602.0				1,602.0
Other comprehensive income	(147.1)					(147.1)
Exercise of stock options and conversion of restricted stock units	259.7	0.2	(135.4)	394.9
Shares purchased under share repurchase program	(3,256.8)		(3,256.8)
Issuance of common stock for employee benefit plans	57.7		39.2	18.5
Expense related to share-based compensation	576.6			576.6
Income tax benefit upon exercise of stock options	302.1			302.1
Balances at end of period at Dec. 31, 2015	$ 5,919.0	$ 9.4	$ (14,051.8)	$ 11,119.3	$ 8,074.4	$ 767.7