Stock-Based Compensation - Summary of Stock-Based Compensation Expense by Type (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock Based Compensation [Line Items]
Total	$ 1,039	$ 1,001	$ 1,657	$ 1,563
Service-based Awards [Member]
Stock Based Compensation [Line Items]
Total	640	865	1,095	1,287
Performance-based Awards - Short-term Incentive Plan [Member]
Stock Based Compensation [Line Items]
Total	138	0	196	0
Performance-based Awards - Long-term Incentive Plan [Member]
Stock Based Compensation [Line Items]
Total	194	77	233	155
Employee Stock Purchase Plan [Member]
Stock Based Compensation [Line Items]
Total	$ 67	$ 59	$ 133	$ 121