Inventories, Net and Significant Suppliers - Changes in Reserve for Excess and Obsolete Inventory (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Schedule of Reserve for Excess and Obsolete Inventory [Rollforward]
Balance at beginning of period	$ 5,138	$ 4,288
Additions charged to costs and expenses	3,978	4,564
Sell through	(643)	(680)
(Write-offs)/Foreign exchange effects	(1,054)	(635)
Balance at end of period	7,419	7,537
Inventory written-off and scrapped during production	$ 3,000	$ 500

Amount of valuation reserve for inventory.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant