Organization and basis of presentation.

No definition available.

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- Definition

Period of sufficient cash to meet its funding requirements.

+ References

No definition available.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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No definition available.

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- Definition

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

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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))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(23)(a)(4))
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-Name Accounting Standards Codification
-Topic 505
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-Subparagraph (SX 210.3-04)
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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Organization and Basis of Presentation - Additional Information (Details) $ in Thousands		6 Months Ended
	Jul. 06, 2018	Jun. 30, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)
Organization And Basis Of Presentation [Line Items]
Number of operating segments \| Segment		1
Unrestricted cash, cash equivalents and investments securities		$ 145,000
Accumulated deficit		$ 64,823	$ 43,380
Minimum
Organization And Basis Of Presentation [Line Items]
Period of sufficient cash to meet its funding requirements		12 months
Common Stock
Organization And Basis Of Presentation [Line Items]
Stock reverse stock split	1-for-3.29
Stock split conversion ratio	0.3040