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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2019 | Mar. 31, 2018
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |
Weighted average grant date fair value of vested options | $ 1.82 |  |
Weighted average grant date fair value of options outstanding | $ 1.82 | $ 1.82 |
Stock-based compensation expense |  | $ 107 | $ 403
Employees [Member] |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |
Stock options granted |  | 0 |

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Grant Date Fair Value + References No definition available. + Details
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Period Type: | instant

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Weighted average grant-date fair value of options vested. + References No definition available. + Details
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- Details
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