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Equity-based Compensation and Equity Incentive Plans - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2020	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee unrecognized compensation expense		$ 6,900
Employee unrecognized compensation cost, period of recognition		2 years 4 months 24 days
Equity-based compensation expense		$ 1,095	$ 954
Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee unrecognized compensation expense		$ 1,300
Employee unrecognized compensation cost, period of recognition		1 year 10 months 24 days
Equity-based compensation expense		$ 220	$ 28
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of discount for employees under ESPP		15.00%
Purchase price as a percentage of fair value under ESPP		85.00%
Options to purchase shares of common stock under ESPP exercised		0
Shares available for future grants		375,519
Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares available for issuance (in shares)	1,613,340
2015 and 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants		1,131,108