Restructuring - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
Feb. 28, 2019	Mar. 31, 2020	Mar. 31, 2019
Restructuring Cost And Reserve [Line Items]
Percent of reduction in headcount of employees	30.00%
Restructuring Charges		$ 0	$ 1,492,000
Cash payments		192,000	608,000
Remaining unpaid liabilities related to restructuring charges		$ 0
Severance And Other Termination Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring Charges			$ 1,492,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

+ References

No definition available.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ 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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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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