Stock-Based Compensation - Board of Director Equity Awards - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended
	May 31, 2021	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vested intrinsic value		$ 2.2	$ 1.9
New Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Common stock issued	61,186
Shares vested, Shares		49,652
Restricted shares vested intrinsic value		$ 0.3