Defined Benefit Plans (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Swiss Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0.2	$ 0.2
Additional employer contributions expected to be paid during the remainder of fiscal year	0.4
Korea Defined Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0.0
Additional employer contributions expected to be paid during the remainder of fiscal year	$ 0.0
Minimum years of service	1 year