Other Current Assets - Schedule of Other Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Advances to vendors	$ 8,578	$ 7,758
Prepaid expenses	1,593	1,438
Other receivables	40	9
Total	$ 10,211	$ 9,205

Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Balance Type:	debit
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