Pension and Other Post-Retirement Benefit Plans (Defined Contribution Plan Expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Defined Contribution Plans [Line Items]
Defined contribution plan expense	$ 5,131	$ 5,300	$ 4,938
Capital accumulation plans [Member]
Schedule of Defined Contribution Plans [Line Items]
Defined contribution plan expense	$ 5,131	$ 5,300	$ 4,938