Foreign Currency Transaction Exposure - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Currency Transaction Gains (Losses) [Line Items]
Currency transaction gains (losses), net	$ 62	$ (6,050)	$ (3,586)	$ (9,558)
Operating income (loss)
Currency Transaction Gains (Losses) [Line Items]
Currency transaction gains (losses), net	1,316	(4,482)	(1,782)	(9,023)
Other non-operating expense, net
Currency Transaction Gains (Losses) [Line Items]
Currency transaction gains (losses), net	$ (1,254)	$ (1,568)	$ (1,804)	$ (535)

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
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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