Pensions and Other Postretirement Benefit Plans (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2008	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Charge to earnings for pension plans		$ 2,500,000
Corridor	10.00%
Threshhold for which margin is added to plan assets	5.00%
Employer contributions	37,200,000
Direct payments to retirees	4,000,000
Accrued pension liability, current	3,576,000		3,764,000
United States
Defined Benefit Plan Disclosure [Line Items]
Accrued postretirement liability	77,900,000
Canada
Defined Benefit Plan Disclosure [Line Items]
Accrued postretirement liability	$ 1,100,000
United States Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of consolidated pension plan assets	67.00%
Percent of consolidated pension plan obligations	60.00%