Employee Benefit Plans (Components of Net Periodic Pension Cost) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pension Plans, Defined Benefit
Components of net periodic benefit cost
Service cost	$ 6	$ 464	$ 1,857
Interest cost	2,205	2,415	2,473
Expected return on plan assets	(3,190)	(3,767)	(3,689)
Amortization of prior service cost	0	196	66
Amortization of net loss	645	1,698	1,660
Curtailment expense (income)	0	984	(36)
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	1,075	0	0
Net periodic benefit cost (income)	741	1,990	2,331
Other Postretirement Benefit Plans, Defined Benefit
Components of net periodic benefit cost
Service cost	143	148	139
Interest cost	295	313	337
Amortization of prior service cost	161	161	161
Net periodic benefit cost (income)	$ 599	$ 622	$ 637