Summary Of Significant Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Change in Accounting Estimate [Line Items]
Equity method intangible asset amortized estimated useful life, years	7
Notional amount of interest rate swap outstanding	57,500,000
Interest rate swap, maturity date	Dec. 22, 2010
Number of employees employed through collective bargaining agreements	2,221
Land, Buildings And Improvements [Member]
Change in Accounting Estimate [Line Items]
Minimum estimated useful lives, years	15
Maximum estimated useful lives, years	40
Machinery And Equipment [Member]
Change in Accounting Estimate [Line Items]
Minimum estimated useful lives, years	3
Maximum estimated useful lives, years	20
Treasury Stock [Member]
Change in Accounting Estimate [Line Items]
Shares paid for statutory minimum tax withholdings related to stock compensation	62,000	68,000	76,000
Unionized Employees Concentration Risk [Member]
Change in Accounting Estimate [Line Items]
Percentage of employees employed through collective bargaining agreements	21.00%
One CBA [Member] | Unionized Employees Concentration Risk [Member]
Change in Accounting Estimate [Line Items]
Percentage of employees employed through collective bargaining agreements	4.00%
Four CBAs [Member] | Unionized Employees Concentration Risk [Member]
Change in Accounting Estimate [Line Items]
Percentage of employees employed through collective bargaining agreements	13.00%