Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Pension Benefit Plan
Change in Projected Benefit Obligation:
Beginning Balance	$ 62,817		$ 56,201
Plan Amendment		[1]		[1]
Service Cost	2,300		2,198		1,575
Interest Cost	2,468		2,417		2,261
Actuarial (Gain) Loss	(9,694)		3,833
Benefits Paid	(1,850)		(1,832)
Ending Balance	56,041		62,817		56,201
Other Benefits Plan
Change in Projected Benefit Obligation:
Beginning Balance	50,608		43,121
Plan Amendment	(10,244)	[1]		[1]
Service Cost	1,338		1,784		1,306
Interest Cost	1,594		1,868		1,604
Actuarial (Gain) Loss	(5,595)		4,425
Benefits Paid	(489)		(590)
Ending Balance	$ 37,212		$ 50,608		$ 43,121

[1] See discussion of Other Benefits Plan amendment in "Other Benefits" above.