Retirement Benefit Plans (Changes in Fair Value of Level 3 Plan Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	$ 172,976
Ending balance	161,369	$ 172,976
Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	1,077	1,196
Unrealized gains relating to instruments still held at the reporting date	(28)	(2)
Benefit payments, administrative expenses, and interest income, net	(115)	(117)
Ending balance	$ 934	$ 1,077