Significant Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 133,476	$ 136,632
Research and development credit carryforwards	28,567	29,242
Capitalized research and development	33,571	27,916
Compensation related items	10,306	12,014
Operating leases	3,462	3,786
Other	9,823	9,056
Total deferred tax assets	219,205	218,646
Valuation allowance	(216,888)	(215,903)
Net deferred tax assets	2,317	2,743
Deferred tax liabilities:
Right-of-use assets	2,173	2,610
Other	209	194
Total deferred tax liabilities	$ 2,382	$ 2,804