Net Loss per Share - Additional Information (Detail) - shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Executive Officers [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Restricted stock units, approved and granted	215,000
Employee Options [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive common stock equivalents	4,925,641	3,932,992

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

No definition available.

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+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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