Stockholders' Equity - Restricted Stock Units - Additional Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Unrecognized stock compensation expense	$ 33.8
Expected weighted average period to recognize unrecognized stock compensation expense	1 year 11 months 23 days
Restricted Stock Units
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Unrecognized stock compensation expense	$ 184.5
Expected weighted average period to recognize unrecognized stock compensation expense	3 years 2 months 8 days
Intrinsic value of restricted stock units vested during the period	$ 11.4

No definition available.

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- Definition

Weighted average 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.

+ 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=109197908&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

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