Employee Benefit Plans (Schedule of Changes in Benefit Obligation and Plan Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Supplemental Executive Retirement Plan [Member]
Benefit obligations:
Beginning of year	$ 8,868	$ 8,102
Service cost	269	232	181
Interest cost	408	431	427
Actuarial loss	1,334	615
Benefits paid	(533)	(512)
End of year	10,346	8,868	8,102
Fair value of plan assets:
Beginning of year
Employer contributions	533	512
Benefits paid	(533)	(512)
End of year
Funded status at end of year, included in other liabilities	10,346	8,868
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss	3,172	1,953
Prior service cost	63	81
Total	3,235	2,034
Other Postretirement Benefit Plan [Member]
Benefit obligations:
Beginning of year	3,187	2,700
Service cost	70	65	60
Interest cost	148	150	143
Actuarial loss	275	417
Benefits paid	(144)	(145)
End of year	3,536	3,187	2,700
Fair value of plan assets:
Beginning of year
Employer contributions	144	145
Benefits paid	(144)	(145)
End of year
Funded status at end of year, included in other liabilities	3,536	3,187
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss	983	739
Prior service cost
Total	$ 983	$ 739