Pension and Other Postretirement Benefit Plans (Textual) (Details) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 6
Pension asset	11,712	$ 11,712	$ 8,887
Estimated future employer contributions in 2018	8	8
Domestic Plan
Defined Benefit Plan Disclosure [Line Items]
Matching contribution, contributory employee savings plan, amount		500	500	$ 600
Swiss Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		$ 615	596
Percentage of total contributions made by employees		45.00%
Accumulated benefit obligation	29,900	$ 29,900	$ 28,900
Estimated future employer contributions in 2018	$ 600	$ 600
Korea Defined Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Service period (in years)		1 year
Postemployment Retirement Benefits | Domestic Plan
Defined Benefit Plan Disclosure [Line Items]
Company matching contribution percentage		50.00%