Leases - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
Apr. 30, 2016	Mar. 31, 2019
Operating Lease Incremental Borrowing Rate Utilized		8.00%
Operating Lease, Payments		$ 29,000
Operating Lease, Weighted Average Remaining Lease Term		2 years 4 months 24 days
Operating Leases, Rent Expense, Net		$ 32,000
Capital Lease Obligations Incurred		113,000
Extended Lab Space [Member]
Operating Lease Monthly Rental Payments		$ 2,575
Lab Space [Member]
Operating Lease Monthly Rental Payments	$ 2,500

Percentage of Operating Lease Incremental Borrowing Rate Utilized.

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- Definition

The amount of the monthly rental payments due under the lease entered.

+ References

No definition available.

+ Details

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- Definition

The increase during the period in capital lease obligations due to entering into new capital leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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