Stockholders' Equity - Restricted Stock Units - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected weighted average period to recognize unrecognized stock compensation expense	1 year 9 months 10 days
Restricted Stock Units
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Grant-date fair value of restricted stock units granted	$ 195.2
Unrecognized stock compensation expense	$ 267.7
Expected weighted average period to recognize unrecognized stock compensation expense	2 years 9 months 7 days
Intrinsic value of restricted stock units vested	$ 100.1	$ 12.7

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=116856206&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

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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