Class of Warrant or Right, Percentage of Shares Issued Available for Purchase

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- Definition

Convertible Preferred Stock, Terms of Conversion, Offering Proceeds

+ References

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- Definition

Convertible Preferred Stock, Terms of Conversion, Share Price

+ References

No definition available.

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- Definition

Number Of Directors Entitled To Elect

+ References

No definition available.

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- Definition

Preferred Stock, Convertible, Conversion Price

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
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- Definition

Number of warrants or rights outstanding.

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-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Number of shares issued for each share of convertible preferred stock that is converted.

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- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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-Publisher FASB
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- Definition

The amount per share used to calculated dividend payments on preferred stock.

+ References

No definition available.

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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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- Definition

The per share liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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Redeemable Convertible Preferred Stock - Narrative (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($) director $ / shares shares	Dec. 31, 2018 USD ($) director $ / shares shares	Dec. 31, 2017 $ / shares shares	Apr. 30, 2016 $ / shares	Dec. 31, 2015 $ / shares	Oct. 31, 2015 $ / shares shares
Temporary Equity [Line Items]
Dividends declared \| $	$ 0	$ 0
Conversion, minimum offering price (in USD per share)	$ 18.31	$ 18.31
Conversion, minimum offering price \| $	$ 50,000,000	$ 50,000,000
Conversion ratio (in shares) \| shares	1	1
Preferred Stock Warrants
Temporary Equity [Line Items]
Percentage of shares purchased available for warrant holders to purchase	50.00%
Warrant exercise price (in USD per share)	$ 6.11	$ 6.11		$ 6.11	$ 6.11	$ 6.11
Time to liquidity (years)	8 years	8 years		7 years 6 months	8 years	8 years
Warrants outstanding (in shares) \| shares	2,667,587	2,672,502	2,672,502			163,877
Series A
Temporary Equity [Line Items]
Number of directors each holders is entitled to elect \| director	2	2
Dividend rate (in USD per share)	$ 0.22	$ 0.22
Per share Preference (in USD per share)	2.70	2.70	$ 2.70
Conversion price (in USD per share)	2.70	2.70
Series A-1
Temporary Equity [Line Items]
Dividend rate (in USD per share)	0.27	0.27
Per share Preference (in USD per share)	3.38	3.38	3.38
Conversion price (in USD per share)	$ 3.38	$ 3.38
Series B
Temporary Equity [Line Items]
Number of directors each holders is entitled to elect \| director	3	3
Dividend rate (in USD per share)	$ 0.49	$ 0.49
Per share Preference (in USD per share)	6.11	6.11	6.11
Conversion price (in USD per share)	$ 6.11	$ 6.11
Series C
Temporary Equity [Line Items]
Number of directors each holders is entitled to elect \| director	2	2
Dividend rate (in USD per share)	$ 0.49	$ 0.49
Per share Preference (in USD per share)	6.11	6.11	$ 6.11
Conversion price (in USD per share)	$ 6.11	$ 6.11