Leases - Schedule of Components of Lease Expense and Related Cash Flows (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease cost	$ 51	$ 102
Short-term lease cost	29	58
Total Lease Cost	80	160
Operating cash flows used for operating leases	$ 52	$ 92