Retirement Benefits (Schedule of Changes in Projected Benefit Obligations) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Benefit obligation, discount rate	0.00%	3.39%
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	$ 64,632	$ 56,787
Interest cost	2,191	2,476	2,716
Benefits paid	(285)	(1,426)
Actuarial loss	(2,221)	6,795
Benefit obligation at end of year	$ 64,317	$ 64,632	$ 56,787