Consolidated Statements of Changes in Equity - USD ($) shares in Millions, $ in Millions	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests	Total
Balance at beginning of period at Dec. 31, 2015	$ 0.3		$ 783.3	$ 2,804.4	$ (349.5)	$ 39.9	$ 3,278.4
Balance (in shares) at Dec. 31, 2015	308.0
Increase (Decrease) In Shareholders' Equity
Net income				822.9		9.7	832.6
Other comprehensive (loss) income					(119.5)	(2.1)	(121.6)
Acquisition resulting in noncontrolling interest						7.5	7.5
Distributions to shareholders of noncontrolling interests						(6.8)	(6.8)
Purchase of treasury stock		$ (325.8)					(325.8)
Purchase of treasury stock (in shares)		(6.0)
Retirement of treasury stock		$ 325.8		(325.8)
Retirement of treasury stock (in shares)	(6.0)	6.0
Stock options exercised, including tax benefit			190.0				190.0
Stock options exercised, including tax benefit (in shares)	6.0
Dividends declared				(178.8)			(178.8)
Stock-based compensation expense			47.6				47.6
Balance at end of period at Dec. 31, 2016	$ 0.3		1,020.9	3,122.7	(469.0)	48.2	3,723.1
Balance (in shares) at Dec. 31, 2016	308.0
Increase (Decrease) In Shareholders' Equity
Net income				650.5		10.2	660.7
Other comprehensive (loss) income					268.0	3.0	271.0
Acquisition resulting in noncontrolling interest						11.1	11.1
Purchase of noncontrolling interest			(5.5)			(10.3)	(15.8)
Distributions to shareholders of noncontrolling interests						(8.6)	(8.6)
Purchase of treasury stock		$ (618.0)					(618.0)
Purchase of treasury stock (in shares)		(8.0)
Retirement of treasury stock		$ 618.0		(618.0)
Retirement of treasury stock (in shares)	(8.0)	8.0
Stock options exercised			183.9				183.9
Stock options exercised (in shares)	6.0
Dividends declared				(213.7)			(213.7)
Stock-based compensation expense			49.7				49.7
Balance at end of period at Dec. 31, 2017	$ 0.3		1,249.0	2,941.5	(201.0)	53.6	$ 4,043.4
Balance (in shares) at Dec. 31, 2017	306.0						305.7
Increase (Decrease) In Shareholders' Equity
Reclassification of income tax effects resulting from the Tax Act (ASU 2018-02) (Note 1)				23.5	(23.5)
Net income				1,205.0		11.9	$ 1,216.9
Other comprehensive (loss) income					(165.7)	(2.7)	(168.4)
Acquisition resulting in noncontrolling interest						0.3	0.3
Purchase of noncontrolling interest			(2.3)			(5.4)	(7.7)
Distributions to shareholders of noncontrolling interests						(10.5)	(10.5)
Purchase of treasury stock		$ (935.2)					(935.2)
Purchase of treasury stock (in shares)		(11.0)
Retirement of treasury stock		$ 880.2		(880.2)
Retirement of treasury stock (in shares)	(10.0)	10.0
Stock options exercised			130.9				130.9
Stock options exercised (in shares)	3.0
Dividends declared				(264.3)			(264.3)
Stock-based compensation expense			55.6				55.6
Balance at end of period at Dec. 31, 2018	$ 0.3	$ (55.0)	$ 1,433.2	3,028.7	$ (390.2)	$ 47.2	$ 4,064.2
Balance (in shares) at Dec. 31, 2018	299.0						298.5
Balance (in shares) at Dec. 31, 2018		(1.0)
Increase (Decrease) In Shareholders' Equity
Cumulative effect of adoption of revenue recognition standard (Note 1) | Impact of ASU 2014-09				$ 3.2			$ 3.2