Leases - Schedule of Future Minimum Rental Payments For Finance and Operating Leases (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Finance Leases, 2019	$ 857
Finance Leases, 2020	836
Finance Leases, 2021	461
Finance Leases, 2022	238
Finance Leases, 2023	12
Finance Leases, Total	2,404
Finance Leases, Less: Imputed interest	(70)
Finance Leases, Total lease liabilities, net of interest	2,334
Operating Leases, 2019	1,743
Operating Leases, 2020	3,282
Operating Leases, 2021	2,880
Operating Leases, 2022	2,458
Operating Leases, 2023	2,197
Operating Leases, Thereafter	7,052
Operating Leases, Total	19,612
Operating Leases, Less: Imputed interest	(2,298)
Operating Leases, Total lease liabilities, net of interest	$ 17,314
2019		$ 4,249
2020		3,232
2021		2,870
2022		2,635
2023		2,346
Thereafter		7,647
Total		$ 22,979