Share-Based Compensation Expense for Stock Awards (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	$ 2,324	$ 2,609	$ 4,863	$ 5,551
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	658	1,160	1,280	2,289
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	$ 1,666	$ 1,449	$ 3,583	$ 3,262