The cumulative amount of the reporting entity's undistributed earnings or deficit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(a)(4))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Balance Type:	credit
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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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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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Risks and Liquidity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended
	Nov. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Unusual Risk or Uncertainty [Line Items]
Accumulated deficit		$ (160,398)	$ (137,860)
Received net proceeds of after deducting underwriting discounts, commissions and other offering expenses	$ 50,700
IPO
Unusual Risk or Uncertainty [Line Items]
Number of shares issued and sold	4,398,700
Public offering price per share	$ 13.00
Over-Allotment Option
Unusual Risk or Uncertainty [Line Items]
Number of shares issued and sold	398,700