Significant Accounting Polices - Additional Information (Details)	12 Months Ended
Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)	Mar. 31, 2019 USD ($)	Jan. 01, 2019 USD ($)
Schedule Of Significant Accounting Policies [Line Items]
Expected term of stock option granted to employees and directors, average contractual term and vesting period	10 years
Impaired of in-process research and development	$ 0	$ 0
Goodwill impairment	0
Uncertain tax positions, accruals	0	0
Accruals for interest or penalties related to income tax matters	$ 0	0
Number of operating segment \| Segment	1
Operating lease liability	$ 589,674			$ 400,000
Operating lease right of use asset	600,000		$ 400,000	$ 400,000
Cash and Cash Equivalents
Schedule Of Significant Accounting Policies [Line Items]
Investments in money market funds	$ 11,600,000	$ 41,700,000

Schedule of significant accounting policies.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an 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.

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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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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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