v3.20.1

Restructuring - Additional Information (Detail)	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2019 Employee	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Oct. 15, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Remaining liability related to severance		$ 793,913	$ 793,913
Chief Executive Officer and Chief Financial and Business Officer [Member]
Restructuring Cost And Reserve [Line Items]
One-time stock-based compensation cumulative reversal for forfeitures of outstanding equity awards		1,051,735	1,100,000
Accounts Payable and Accrued Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Remaining liability related to severance		$ 800,000	800,000
Workforce Reduction [Member]
Restructuring Cost And Reserve [Line Items]
Realignment plan, number of current workforce reduced | Employee	11
Realignment plan, number of workforce reduced, period percent	41.00%
Realignment plan, employee severance expense			900,000
Estimated employee related costs				$ 1,000,000
Cash payments against severance liability			$ 1,100,000

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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The number of positions eliminated during the period as a result of restructuring activities.

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