Assets Held for Sale (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Proceeds from sales of assets	$ 0	$ 8.9
Property, plant and equipment held for sale [Abstract]
Assets held-for-sale, property, plant and equipment	167.9		167.9
Assets held for sale acumulated depreciation	(135.4)		(135.4)
Assets Held For Sale Property Plant and Equipment Net	32.5		32.5
Land Land Improvements And Logging Roads Net of Road Amortization [Member]
Property, plant and equipment held for sale [Abstract]
Assets held-for-sale, property, plant and equipment	10.0		10.0
Building [Member]
Property, plant and equipment held for sale [Abstract]
Assets held-for-sale, property, plant and equipment	17.1		17.1
Machinery and Equipment [Member]
Property, plant and equipment held for sale [Abstract]
Assets held-for-sale, property, plant and equipment	$ 140.8		$ 140.8