Stockholders' Equity and Employee Benefit Plans - Unamortized Stock-based Compensation (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 119,162
Weighted average vesting period (in years)	1 year 1 month 6 days
Restricted Stock Units (Service-Based)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 70,735
Weighted average vesting period (in years)	2 years 10 months 24 days
Restricted Stock Units (Performance-Based)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 6,162
Weighted average vesting period (in years)	1 year 1 month 6 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 34,501
Weighted average vesting period (in years)	2 years 2 months 12 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 4,115
Weighted average vesting period (in years)	2 years 3 months 18 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation (in thousands)	$ 3,649
Weighted average vesting period (in years)	1 year 3 months 18 days

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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