Employee Benefits - Schedule of Reconciliation of Changes in Present Value of Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ (524)	$ (441)	$ (492)
Interest cost	(37)	(22)	(33)
Actuarial gains (losses)	(1,335)	128	512
Amortization of net loss (gain)	0	0	12
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actuarial gains (losses)	(1,335)	128	512
Research and Development Expense
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	(211)	(163)	(167)
Sales And Operations Expense
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	(144)	(153)	(188)
General and Administrative Expense
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	(169)	(125)	(137)
Interest Income (Expense)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	$ (37)	$ (22)	$ (33)