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Stock Based Compensation - Restricted Stock Units - Additional Information (Detail) - Restricted Stock Units (RSUs) [Member] | 6 Months Ended
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Jun. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Employee service share-based compensation, nonvested awards, compensation not yet recognized, share-based awards other than options | $ | $ 7,576,429
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition | 1 year 4 months 24 days
2013 Equity Incentive Plan [Member] | Minimum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Share-based compensation arrangement by share-based payment award, award vesting period | 2 years
2013 Equity Incentive Plan [Member] | Maximum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Share-based compensation arrangement by share-based payment award, award vesting period | 4 years
2013 Equity Incentive Plan [Member] | Employee [Member] | Common Stock [Member] |
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, grants in period | 645,031
2017 Equity Inducement Plan [Member] | Employee [Member] |
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, grants in period | 113,000
Share-based compensation arrangement by share-based payment award, award vesting period | 4 years

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. + 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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=120381028&loc=d3e5070-113901 + Details
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