Redeemable Convertible Preferred Stock and Stockholders' Equity - Summary of Significant Unobservable Inputs (Details)	3 Months Ended
Mar. 31, 2017
Fair Value Inputs, Equity, Quantitative Information [Line Items]
Discount rate	20.00%
Income Approach Valuation Technique
Fair Value Inputs, Equity, Quantitative Information [Line Items]
Probability of redemption, private company	12.50%
Market Approach Valuation Technique
Fair Value Inputs, Equity, Quantitative Information [Line Items]
Probability of redemption, private company	12.50%
Probability Weighted Expected Return Method
Fair Value Inputs, Equity, Quantitative Information [Line Items]
PWERM (IPO)	60.00%
PWERM (IPO)	15.00%
Minimum
Fair Value Inputs, Equity, Quantitative Information [Line Items]
IPO revenue multiple	2.8
Forecasted revenue growth rate	31.10%
Maximum
Fair Value Inputs, Equity, Quantitative Information [Line Items]
IPO revenue multiple	3.0
Forecasted revenue growth rate	40.00%

Fair Value Inputs, Probability of Redemption, Initial Public Offering

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Fair Value Inputs, Probability of Redemption, Mergers and Acquisitions

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Fair Value Inputs, Probability of Redemption, Private Company

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Percentage of assumed long-term growth in revenues, used as an input to measure fair value.

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Market valuation of entity divided by revenue, used as an input to measure fair value.

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