Related Party Transactions - The 2024 Convertible Notes (Details) - 2024 Convertible Notes - USD ($) $ / shares in Units, $ in Thousands	Oct. 29, 2018	Dec. 31, 2018
The 2024 Convertible Notes
Aggregate principal amount	$ 25,000	$ 25,000
Conversion price (in dollars per share)	$ 8.00
Prior written notice (in days)	10 days
From and after April 29, 2019 To October 29, 2019
The 2024 Convertible Notes
Interest rate (in percent)	12.00%
Prior written notice (in days)	10 days
From and after October 29, 2019
The 2024 Convertible Notes
Interest rate (in percent)	16.00%
Prior written notice (in days)	10 days

Notice period to prepay the convertible notes.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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-Name Accounting Standards Codification
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-Section S99
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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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