Summary of Option Activity (Details) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Options \| shares	14.0
Granted, Options \| shares	1.8
Exercised, Options \| shares	(2.9)
Cancelled, Options \| shares	(0.1)
Ending Balance, Options \| shares	12.8
Exercisable at September 30, 2020, Options \| shares	7.6
Beginning Balance, Weighted-Average Exercise Price \| $ / shares	$ 43.23
Granted, Weighted-Average Exercise Price \| $ / shares	73.98
Exercised, Weighted-Average Exercise Price \| $ / shares	30.21
Cancelled, Weighted-Average Exercise Price \| $ / shares	62.17
Ending Balance, Weighted-Average Exercise Price \| $ / shares	50.48
Exercisable at September 30, 2020 Weighted-Average Exercise Price \| $ / shares	$ 39.71
Outstanding at September 30, 2020, Weighted-Average Remaining Contractual Term, years	6 years
Exercisable at September 30, 2020, Weighted-Average Remaining Contractual Term, years	4 years 2 months 12 days
Outstanding at September 30, 2020, Aggregate Intrinsic Value \| $	$ 553.2
Exercisable at September 30, 2020, Aggregate Intrinsic Value \| $	$ 410.2

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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