Defined Contribution and Deferred Compensation Plans - Additional Information (Detail) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018  | 
Dec. 31, 2017  | 
Dec. 31, 2016  | 
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| Defined Contribution Plan Disclosure [Line Items] | |||
| Silvercrest matching contributions towards benefit of employees | $ 86 | $ 75 | $ 112 | 
| Defined contribution plan, plan name | 401(k) savings plan | ||
| Maximum | |||
| Defined Contribution Plan Disclosure [Line Items] | |||
| Silvercrest matching contribution percentage | 4.00% | ||
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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 discretionary contributions made by an employer to a defined contribution plan. No definition available. 
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- Definition Percentage employer matches of the employee's percentage contribution matched. No definition available. 
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- Definition Name of defined contribution plan designed to provide retirement benefits. Includes, but is not limited to, legal name of plan. No definition available. 
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- Details 
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