Equity - Share Repurchases, Dividends, Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended		3 Months Ended						9 Months Ended
	Oct. 24, 2023	Oct. 24, 2023	Feb. 28, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Oct. 30, 2023
Share Repurchase Plan
Value of shares authorized by the Board of Directors to be repurchased under share repurchase plan												$ 1,500.0
Share repurchases (in shares)		575,060		467,213	308,454	160,224	1,883,093	1,085,635	113,529	935,891	3,082,257
Average costs per share		$ 255.15		$ 270.49	$ 239.55	$ 242.86	$ 178.79	$ 178.61	$ 150.97	$ 255.56	$ 177.70
Value of shares repurchased		$ 146.7		$ 126.4	$ 73.9	$ 38.9	$ 336.7	$ 193.9	$ 17.1	$ 239.2	$ 547.7
Remaining value of shares authorized by the Board of Directors to be repurchased under share repurchase plan	$ 294.8	$ 294.8
Common Stock and Additional Paid-In (in Shares)
Payments made to tax authorities on employees' behalf										$ 41.3	$ 21.6
Dividends
Common stock quarterly dividend per share (in dollars per share)				$ 1.00			$ 0.875			$ 3.00	$ 2.625
Common stock dividend quarterly declared and paid per share (in dollars per share)	$ 1.00			$ 1.00			$ 0.875			$ 3.00	$ 2.625
Dividends paid				$ 58.5			$ 52.5			$ 176.1	$ 160.6
Additional share-based compensation disclosures
Total unrecognized compensation cost				82.5						$ 82.5
Weighted average recognition period for unrecognized compensation cost (in years)										1 year 8 months 12 days
Common Stock and Additional Paid in Capital
Share Repurchase Plan
Value of shares repurchased				$ 11.6			$ 14.1			$ 5.3	26.8
Restricted stock units (RSUs)
Dividends
Dividend equivalents paid										$ 3.2	$ 2.9
Additional share-based compensation disclosures
Vesting period (in years)			3 years
Changes
Granted (in shares)			109,683
Restricted stock units (RSUs) and performance stock units (PSUs)
Changes
Unvested at the beginning of the year (in units)						582,012				582,012
Granted (in shares)										193,812
Vested (in units)										(4,075)
Cancelled or forfeited (in units)										(13,693)
Unvested at the end of the period (in units)				758,056						758,056
Shares reserved for future grants (all plans)				1,479,570						1,479,570
Weighted Average Grant Date Fair Value
Unvested at the beginning of the year (in dollars per unit)						$ 164.60				$ 164.60
Granted (in dollars per unit)										247.90
Vested (in dollars per unit)										157.22
Cancelled or forfeited (in dollars per unit)										177.18
Unvested at the end of the period (in dollars per unit)				$ 185.71						$ 185.71
Performance stock units (PSUs)
Additional share-based compensation disclosures
Vesting period (in years)			3 years							3 years
Return on assets result period			3 years							3 years	3 years
Changes
Granted (in shares)			84,129
Performance stock units (PSUs) | Maximum
Stock Based Compensation
Share of Common Stock			2							2	2
All stock-based compensation plans
Common Stock and Additional Paid-In (in Shares)
Payments made to tax authorities on employees' behalf										$ 41.3	$ 21.6