Schedule of Prepayments and Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Prepaid And Other Current Assets [Line Items]
Contract manufacturer and supplier prepayments	$ 102,652	$ 82,503
Prepaid taxes	10,709	5,039
Prepaid maintenance and other services	7,802	8,189
Other prepayments	12,439	12,386
Total prepayments	$ 133,602	$ 108,117

Amount of asset related to consideration paid in advance for income and other taxes 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
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant