Employee Benefit Plans (Reconciliation of the Projected Benefit Obligation) (Details) (Other Postretirement Benefit Plans, Defined Benefit, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan, Change in Benefit Obligation
Benefit obligation at beginning of plan year	$ 6,542	$ 6,459
Service cost	143	148	139
Interest cost on projected benefit obligations	(295)	(313)	(337)
Actuarial (gain) loss	422	(1)
Plan participants contributions	673	718
Benefits paid	(1,135)	(1,095)
Benefit obligation and funded status at end of year	$ 6,940	$ 6,542	$ 6,459