Stockholders' Equity - Restricted Stock Units - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected weighted average period to recognize unrecognized stock compensation expense			1 year 6 months 18 days
Restricted Stock Units
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Grant-date fair value of restricted stock units granted			$ 73.0	$ 62.0
Unrecognized stock compensation expense	$ 277.6		$ 277.6
Expected weighted average period to recognize unrecognized stock compensation expense			2 years 5 months 15 days
Fair value of restricted stock units vested	$ 20.5	$ 10.0	$ 37.6	$ 17.6

Share based compensation arrangement by share based payment award equity instruments other than options granted in period at fair value.

No definition available.

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- References

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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