Retirement Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
U.S. Pension and Postretirement Health Care
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 18	$ 17	$ 35	$ 35
Interest cost	673	695	1,390	1,489
Expected return on plan assets	(1,205)	(1,141)	(2,482)	(2,408)
Amortization of actuarial loss	274	190	585	434
Amortization of prior service credit	(15)	(17)	(29)	(36)
Total	(255)	(256)	(501)	(486)
Non-U.S. Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	40	50	79	99
Expected return on plan assets	(71)	(75)	(141)	(149)
Amortization of actuarial loss	12	19	23	35
Total	$ (19)	$ (6)	$ (39)	$ (15)