Retirement Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
U.S. Pension and Postretirement Health Care
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 17	$ 17
Interest cost	718	717
Expected return on plan assets	(1,270)	(1,277)
Amortization of actuarial loss	283	311
Amortization of prior service credit	(12)	(14)
Total	(264)	(246)
Non-U.S. Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	35	39
Expected return on plan assets	(60)	(70)
Amortization of actuarial loss	6	11
Total	$ (19)	$ (20)