Shareholders' Equity and Noncontrolling Interests (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 20, 2020	Jul. 23, 2019	Jul. 22, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			$ 4,203.2	$ 4,800.3	$ 4,203.2	$ 4,596.2	$ 4,064.2
Net income				349.5	282.3	853.1	843.2
Other comprehensive income (loss)				108.5	(98.7)	44.0	(105.5)
Acquisitions resulting in noncontrolling interest					1.2	0.3	11.2
Purchase of noncontrolling interest						(7.3)	(21.4)
Distributions to shareholders of noncontrolling interests				(1.9)	(0.4)	(4.2)	(3.6)
Purchase of treasury stock				(201.9)	(150.0)	(459.2)	(558.7)
Retirement of treasury stock				0.0	0.0	0.0	0.0
Stock options exercised				106.4	30.9	258.3	146.1
Dividends declared				(74.7)	(74.0)	(223.2)	(210.8)
Stock-based compensation expense				19.0	16.6	51.0	46.4
Balance at end of period				$ 5,105.2	$ 4,211.1	$ 5,105.2	$ 4,211.1
Dividends [Abstract]
Dividends declared per share (in dollars per share)		$ 0.25	$ 0.23	$ 0.25	$ 0.25	$ 0.75	$ 0.71
Common Stock
Increase (Decrease) In Shareholders' Equity
Balance (in shares)			298.4	298.5	298.4	298.7	299.2
Balance at beginning of period			$ 0.3	$ 0.3	$ 0.3	$ 0.3	$ 0.3
Retirement of treasury stock				$ 0.0	$ 0.0	$ 0.0	$ 0.0
Number of treasury shares retired				0.9	1.7	3.6	5.1
Stock options exercised				$ 0.0	$ 0.0	$ 0.0	$ 0.0
Stock options exercised (in shares)				1.7	0.5	4.2	3.1
Balance (in shares)				299.3	297.2	299.3	297.2
Balance at end of period				$ 0.3	$ 0.3	$ 0.3	$ 0.3
Additional Paid-In Capital
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			1,541.8	1,834.5	1,541.8	1,683.3	1,433.2
Purchase of noncontrolling interest						(2.1)	(17.5)
Stock options exercised				84.6	27.2	205.9	123.5
Stock-based compensation expense				19.0	16.6	51.0	46.4
Balance at end of period				1,938.1	1,585.6	1,938.1	1,585.6
Retained Earnings
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			3,104.6	3,419.4	3,104.6	3,348.4	3,028.7
Net income				346.6	280.3	846.4	836.3
Retirement of treasury stock				(91.6)	(150.0)	(348.9)	(471.1)
Stock options exercised				(12.6)	(2.2)	(31.8)	(24.4)
Dividends declared				(74.7)	(74.0)	(223.2)	(210.8)
Balance at end of period				3,587.1	3,158.7	3,587.1	3,158.7
Accumulated Other Comprehensive Loss
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			(396.9)	(494.6)	(396.9)	(430.9)	(390.2)
Other comprehensive income (loss)				106.2	(96.8)	42.5	(103.5)
Balance at end of period				(388.4)	(493.7)	(388.4)	(493.7)
Treasury Stock
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			$ (101.5)	$ (21.0)	$ (101.5)	$ (70.8)	$ (55.0)
Balance (in shares)			(1.2)	(0.2)	(1.2)	(0.8)	(0.7)
Purchase of treasury stock				$ (201.9)	$ (150.0)	$ (459.2)	$ (558.7)
Purchase of treasury stock (in shares)				(1.9)	(1.7)	(4.6)	(6.1)
Retirement of treasury stock				$ 91.6	$ 150.0	$ 348.9	$ 471.1
Number of treasury shares retired				0.9	1.7	3.6	5.1
Stock options exercised				$ 34.4	$ 5.9	$ 84.2	$ 47.0
Stock options exercised (in shares)				0.3	0.1	0.9	0.6
Balance at end of period				$ (96.9)	$ (95.6)	$ (96.9)	$ (95.6)
Balance (in shares)				(0.9)	(1.1)	(0.9)	(1.1)
Noncontrolling Interests
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period			$ 54.9	$ 61.7	$ 54.9	$ 65.9	$ 47.2
Net income				2.9	2.0	6.7	6.9
Other comprehensive income (loss)				2.3	(1.9)	1.5	(2.0)
Acquisitions resulting in noncontrolling interest					1.2	0.3	11.2
Purchase of noncontrolling interest						(5.2)	(3.9)
Distributions to shareholders of noncontrolling interests				(1.9)	(0.4)	(4.2)	(3.6)
Balance at end of period				$ 65.0	$ 55.8	65.0	$ 55.8
Subsequent Event
Dividends [Abstract]
Dividends declared per share (in dollars per share)	$ 0.29
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 [Member]
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period						(3.8)
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 [Member] | Retained Earnings
Increase (Decrease) In Shareholders' Equity
Balance at beginning of period						$ (3.8)