Share-Based Compensation - Summary of Activity Related to RSU Awards (Detail) - Restricted Stock Units [Member]	9 Months Ended
Sep. 30, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Awards outstanding, Beginning balance \| shares	23,333
Number of Shares, Vested \| shares	(11,666)
Number of Shares, Awards outstanding, Ending balance \| shares	11,667
Number of Shares, RSUs expected to vest \| shares	11,564
Weighted-Average Grant Date Fair Value, Awards outstanding, Beginning balance \| $ / shares	$ 5.81
Weighted-Average Grant Date Fair Value, Vested \| $ / shares	5.81
Weighted-Average Grant Date Fair Value, Awards outstanding, Ending balance \| $ / shares	5.81
Weighted-Average Grant Date Fair Value, RSUs expected to vest \| $ / shares	$ 5.81

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=116856206&loc=d3e5070-113901

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options expected to vest outstanding number.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options expected to vest weighted average grant date fair value.

+ References

No definition available.

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