Pension and Severance Plans (Details) - Foreign Pension Plans [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 8,170	$ 1,219
Interest cost	904	766
Expected return on plan assets	(947)	(856)
Amortization of prior service cost	9	9
Recognized actuarial loss	24	21
Net periodic pension cost	$ 8,160	$ 1,159