Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions |
12 Months Ended | |||
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Jan. 01, 2008 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Employee contribution percentage | 4.00% | |||
| Employer matching contribution | $ 0.2 | $ 0.2 | $ 0.1 | |
| National Holdings [Member] | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent | 75.00% | |||
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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. No definition available.
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. No definition available.
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. No definition available.
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- Details
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