Accrued Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Schedule of Accrued Liabilities [Line Items]
Legal and accounting fees	$ 81	$ 45
Accrued compensation	973	1,294
Lease liability	39
Accrued research and development costs and other		173
Total	$ 1,093	$ 1,512