INCOME TAXES - Details of Significant Components of Net Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss carryforwards	$ 9,239	$ 4,936
State income taxes	1	1
Deferred revenue	5,426	6,291
Research and development and other credits	8,638	8,282
Reserve and accruals recognized in different periods	1,027	1,128
Capitalized research and development expenses	3,318	3,447
Depreciation and amortization	3,134	3,636
Lease liability	351	806
Total deferred tax assets	31,134	28,527
Valuation allowance	(28,475)	(28,057)
Deferred tax liabilities:	2,659	470
Right of use lease assets	(344)	(466)
Foreign credits	(14)	(23)
Other deferred tax liabilities	0	(40)
Total deferred tax liabilities	(358)	(529)
Net deferred taxes		$ (59)
Net deferred taxes	$ 2,301