Defined Contribution and Deferred Compensation Plans - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Contribution Plan Disclosure [Line Items]
Silvercrest matching contributions towards benefit of employees	$ 22	$ 19
Defined contribution plan, plan name	401(k) savings plan
Maximum
Defined Contribution Plan Disclosure [Line Items]
Silvercrest matching contribution percentage	4.00%