Supplemental Financial Information - Currency Transaction Gains (Losses) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Currency Transaction Gains (Losses) [Line Items]
Net transaction losses	$ (8,389)	$ (36,203)	$ (191,332)
Operating loss
Currency Transaction Gains (Losses) [Line Items]
Net transaction losses	(5,061)	(29,678)	(164,042)
Other non-operating expense, net
Currency Transaction Gains (Losses) [Line Items]
Net transaction losses	$ (3,328)	$ (6,525)	$ (27,290)

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894

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