Stockholders' Equity - Schedule of Unrecognized Compensation Expense, Net of Forfeitures, Expected to be Recognized Over Weighted-average Periods (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Stock options
Stock-based compensation
Unrecognized Compensation Expense	$ 1,304
Unrecognized Compensation Weighted-Average Period (in years)	2 years 4 months 24 days
RSUs
Stock-based compensation
Unrecognized Compensation Expense	$ 1,241
Unrecognized Compensation Weighted-Average Period (in years)	1 year 7 months 6 days

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.

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

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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