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Stock-Based Compensation - Additional Information (Detail) - USD ($) | May 17, 2018 | Sep. 30, 2018
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Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share based compensation arrangement By share based payment award equity instruments other than options outstanding number |  | 10,057
Shares available for future grant under the plan |  | 495,730
Director |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share based compensation arrangement by share based payment award non option equity instruments granted per director | 195 |
Share based compensation arrangement by share based payment award non option equity instruments grant date fair value per grant | $ 56,250 |
Share based compensation arrangement By share based payment award non option equity instruments grant date fair value total | $ 394,000 |

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Grant Date Fair Value Total + References No definition available. + Details
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- Definition Number of restricted stock units granted to each of the members of the board of directors during the period. + References No definition available. + Details
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- Definition Number of equity instruments other than options outstanding, including both vested and non-vested instruments. + 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)(1)(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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