Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Inventory cost	$ 6,923	$ 7,944
Accrued expenses and accounts receivable	2,112	2,206
Foreign tax credits	19,610	20,133
Research and development tax credits	13,633	12,306
Net operating loss carryforwards	37,379	25,878
Accrued pension	5,494	7,169
Share based compensation and others	16,992	18,238
Total deferred tax assets, include valuation allowance	102,143	93,874
Valuation allowances	(32,082)	(35,738)
Total deferred tax assets, non-current	70,061	58,136
Deferred tax liabilities
Plant, equipment and intangible assets	(28,639)	(39,722)
Total deferred tax liabilities, non-current	(28,639)	(39,722)
Net deferred tax assets	$ 41,422	$ 18,414