Stock-Based Compensation - Fair Value Assumptions (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Stock-based compensation
Unamortized stock-based compensation expense not yet recognized	$ 62.9
RSU
Stock-based compensation
Unamortized stock-based compensation expense not yet recognized	$ 35.4
Options remaining vesting period	4 years
Weighted average period of recognition	3 years
Stock options
Stock-based compensation
Unamortized stock-based compensation expense not yet recognized	$ 27.5
Options remaining vesting period	4 years
Weighted average period of recognition	2 years 1 month 6 days

Remaining vesting period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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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 option under share-based payment arrangement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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