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Retirement Plan - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |
Retirement plan, employees maximum pre-tax contributions percentage | 60.00% |  |
Contributions to 401(k) plan | $ 0 | $ 0 | $ 0
401 (K) Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Retirement plan, employees maximum pre-tax contributions percentage | 6.00% |  |
Employer matching contribution, percent of employee's contribution | 50.00% |  |
Maximum annual contributions per employee, amount | $ 5,000 |  |

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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 Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Maximum amount the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Details
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