Share Repurchases and Dividends (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Oct. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 31, 2017
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased (in shares)			2,200,000	1,200,000
Amount paid			$ 252.2	$ 98.8
Weighted average cost per share (in dollars per share)			$ 116.09	$ 85.06
Shares adding to existing share repurchase program						$ 2,000.0
Shares pending settlement (in shares)		0	0	0
Remaining authorized purchase capacity			$ 1,700.0
Reduction in shares unissued				$ 0.0
Quarterly dividend per share (in dollars per share)	$ 0.46		$ 1.77	$ 1.66	$ 1.56
Cash dividends declared			$ 563.0	$ 528.8	$ 499.4
Quarterly dividend payable		$ 135.5	$ 145.9	$ 135.5
Treasury Stock
Equity, Class of Treasury Stock [Line Items]
Shares returned to unissued status (in shares)		35,789,806		(35,800,000)
Reduction in shares unissued		$ 2,316.0		$ (2,316.0)
Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares returned to unissued status (in shares)				35,800,000
Reduction in shares unissued		0.3		$ 0.3
Additional Paid-In Capital
Equity, Class of Treasury Stock [Line Items]
Reduction in shares unissued		$ 2,315.7		$ 2,315.7