Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Raw material	$ 78,716	$ 82,397
Work in process	53,121	42,304
Finished goods	157,113	163,956
Total	$ 288,950	$ 288,657	[1]

[1] December 31, 2017 balances were derived from audited consolidated financial statements.