Retirement Plan (Net Periodic Pension Expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012 Defined Benefit Retirement Plan	Dec. 31, 2011 Defined Benefit Retirement Plan	Dec. 31, 2012 Other Post-Retirement Healthcare and Other Benefits Plan	Dec. 31, 2011 Other Post-Retirement Healthcare and Other Benefits Plan	Dec. 31, 2010 Other Post-Retirement Healthcare and Other Benefits Plan	Dec. 31, 2012 Periodic Pension Expense Defined Benefit Retirement Plan	Dec. 31, 2011 Periodic Pension Expense Defined Benefit Retirement Plan	Dec. 31, 2010 Periodic Pension Expense Defined Benefit Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost – benefit earned during the year		$ 679	$ 5,070	$ 1,892	$ 1,569	$ 926	$ 679	$ 5,070	$ 4,595
Interest cost on projected benefit obligations		3,962	5,125	3,519	2,193	351	3,962	5,125	5,154
Amortization of transition obligation				0	44	44
Expected return on plan assets							(3,798)	(5,230)	(4,576)
Amortization of prior service cost	0			(2,221)	0	0	67	390	390
Amortization of net loss	2,771			269	114	98	1,933	2,126	2,196
Effect of settlements							2,855	3,951	0
Effect of curtailment		7,102	15,151				899	1,065	0
Net periodic pension expense				$ 3,459	$ 3,920	$ 1,419	$ 6,597	$ 12,497	$ 7,759