Stock-Based Compensation - Summary of Restricted Stock Activity (Detail) - Restricted stock [Member]	6 Months Ended
Jun. 30, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Unvested, Beginning balance \| shares	183,095
Shares, Unvested, Ending balance \| shares	183,095
Weighted-Average Grant Date Fair Value, Unvested, Beginning balance \| $ / shares	$ 0.17
Weighted-Average Grant Date Fair Value, Unvested, Ending balance \| $ / shares	$ 0.17

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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- Definition

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.

+ References

No definition available.

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