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Equity - Share Repurchases, Dividends, Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended			3 Months Ended			6 Months Ended
	Apr. 26, 2022	Jul. 25, 2022	Mar. 31, 2022	Jan. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jul. 26, 2022	Jul. 20, 2021
Share Repurchase Plan
Value of shares authorized by the Board of Directors to be repurchased under share repurchase plan										$ 1,000.0	$ 1,000.0
Share repurchases (in shares)					1,085,635	113,529	147,016	1,199,164	147,016
Average costs per share					$ 178.61	$ 150.97	$ 163.50	$ 176.00	$ 163.50
Value of shares repurchased					$ 193.9	$ 17.1	$ 24.0	$ 211.0	$ 24.0
Remaining value of shares authorized by the Board of Directors to be repurchased under share repurchase plan		$ 401.6
Common Stock and Additional Paid-In (in Shares)
Payments made to tax authorities on employees' behalf								$ 17.1	$ 8.3
Dividends
Common stock quarterly dividend per share (in dollars per share)					$ 0.875		$ 0.6875	$ 1.75	$ 1.375
Common stock dividend quarterly declared and paid per share (in dollars per share)	$ 0.875				$ 0.875		$ 0.6875	$ 1.75	$ 1.375
Dividends paid					$ 53.9		$ 43.8	$ 108.1	$ 87.6
Subsequent event
Share Repurchase Plan
Share repurchases (in shares)		581,648
Average costs per share		$ 171.94
Value of shares repurchased		$ 100.0
Common Stock and Additional Paid in Capital
Share Repurchase Plan
Value of shares repurchased					$ 18.0		$ 24.0	12.7	24.0
Restricted stock units (RSUs)
Dividends
Dividend equivalents paid								$ 2.5	$ 1.0
Stock-Based Compensation
Vesting period (in years)			3 years	3 years
Changes
Granted (in units)			136,346	56,452
Weighted Average Grant Date Fair Value
Granted (in dollars per unit)			$ 195.28	$ 152.21
Restricted stock units (RSUs) and performance stock units (PSUs)
Changes
Unvested at the beginning of the year (in units)		1,090,610		831,597		831,597		831,597
Granted (in units)								305,249
Vested (in units)								(24,363)
Cancelled or forfeited (in units)								(21,873)
Unvested at the end of the period (in units)					1,090,610			1,090,610
Shares reserved for future grants (all plans)					1,566,598			1,566,598
Weighted Average Grant Date Fair Value
Unvested at the beginning of the year (in dollars per unit)		$ 128.10		$ 105.12		$ 105.12		$ 105.12
Granted (in dollars per unit)								187.31
Vested (in dollars per unit)								95.75
Cancelled or forfeited (in dollars per unit)								116.61
Unvested at the end of the period (in dollars per unit)					$ 128.10			$ 128.10
Aggregate Fair Value
Unvested at the end of the period					$ 249.4			$ 249.4
Number of shares of common stock that were unsettled								58,618
Performance stock units (PSUs)
Stock-Based Compensation
Vesting period (in years)			3 years					3 years	3 years
Changes
Granted (in units)			112,451
Weighted Average Grant Date Fair Value
Granted (in dollars per unit)			$ 195.28
Performance stock units (PSUs) \| Maximum
Stock Based Compensation
Share of Common Stock								2
All stock-based compensation plans
Common Stock and Additional Paid-In (in Shares)
Payments made to tax authorities on employees' behalf								$ 17.1	$ 8.3