Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Inventory, Net [Abstract]
Raw materials	$ 328,080	$ 310,204
Work in process	192,993	191,660
Finished goods	218,408	205,814
Less: Excess and obsolete reserve	(78,644)	(73,807)
Inventories, net	660,837	633,871
Inventory Write-down	$ 17,100	$ 16,200	$ 22,900