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Fair Value Measurements - Summary of Changes in Fair Value of Level 3 Liability (Details) - Recurring - Level 3 $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 1,671
Revaluation of convertible preferred stock liability recorded in other expenses (income), net	30,597
Partial settlement of convertible preferred stock liability upon third closing	(6,673)
Capital contribution related to extinguishment of preferred stock liability	$ (25,595)

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- Definition

Fair value measurement with unobservable inputs reconciliation capital contribution related to the extinguishment of preferred stock liability.

+ References

No definition available.

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- Definition

Fair value measurement with unobservable inputs reconciliation partial settlement of convertible preferred stock liability upon third closing.

+ References

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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.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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