Changes in Equity and Noncontrolling Interests (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period	$ 3,278.4	$ 2,937.9
Net income	158.4	181.8
Other comprehensive income (loss)	52.4	(65.7)
Distributions to shareholders of noncontrolling interests	(4.0)	(3.2)
Purchase of treasury stock	(49.2)	(62.2)
Stock options exercised, including tax benefit	19.6	19.3
Dividends declared	(43.0)	(38.8)
Stock-based compensation expense	11.6	10.1
Balance at end of period	$ 3,424.2	$ 2,979.2
Common Stock
Increase (Decrease) In Shareholders' Equity
Balance (in shares)	308.0	309.9
Balance at beginning of period	$ 0.3	$ 0.3
Retirement of treasury stock (in shares)	(1.0)	(1.1)
Stock options exercised, including tax benefit (in shares)	0.7	0.6
Balance (in shares)	307.7	309.4
Balance at end of period	$ 0.3	$ 0.3
Additional Paid in Capital
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period	783.3	659.4
Stock options exercised, including tax benefit	19.6	19.3
Stock-based compensation expense	11.6	10.1
Balance at end of period	814.5	688.8
Retained Earnings
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period	2,804.4	2,453.5
Net income	156.6	179.8
Retirement of treasury stock	(49.2)	(62.2)
Dividends declared	(43.0)	(38.8)
Balance at end of period	2,868.8	2,532.3
Accumulated Other Comprehensive Loss
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period	(349.5)	(205.8)
Other comprehensive income (loss)	52.1	(65.7)
Balance at end of period	(297.4)	(271.5)
Treasury Stock
Increase (Decrease) In Shareholders' Equity
Purchase of treasury stock	(49.2)	(62.2)
Retirement of treasury stock	49.2	62.2
Noncontrolling Interests
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period	39.9	30.5
Net income	1.8	2.0
Other comprehensive income (loss)	0.3
Distributions to shareholders of noncontrolling interests	(4.0)	(3.2)
Balance at end of period	$ 38.0	$ 29.3