Leases - Summary of Future Minimum Lease Payments under Non-Cancellable Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Remainder of 2019	$ 326
2020	1,252
2021	1,014
2022	779
2023	424
2024 and thereafter	1,626
Total lease payments	5,421
Less: Interest	(485)
Present value of lease liabilities	$ 4,936
2019		$ 1,085
2020		949
2021		892
2022		651
2023		346
Thereafter		867
Total		$ 4,790

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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