Leases - Summary of Future Minimum Lease Payments under Non-Cancellable Leases (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Remainder of 2019	$ 955
2020	1,174
2021	938
2022	723
2023	395
2024 and thereafter	1,626
Total lease payments	5,811
Less: Interest	(542)
Present value of lease liabilities	$ 5,269
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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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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