Retirement Plan (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Jun. 30, 2012	Sep. 30, 2012	Sep. 30, 2011
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	$ 0	$ 9,000	$ 700,000	$ 0	$ 9,000
Other Comprehensive Income (Loss), Finalization of Pension and Non-Pension Postretirement Plan Valuation, before Tax				7,102,000
Expected long-term annual rate of return on plan assets				6.50%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated contributions in 2012			22,400,000
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Amendments	3,200,000			10,100,000
Estimated effect of curtailment	$ 0	$ 798,000	$ 7,100,000	$ 899,000	$ 798,000