Summary of Significant Accounting Policies Assets Held for Sale (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Assets Held-for-sale, Property, Plant and Equipment	$ 167.9	$ 214.3
Accumulated depreciation	135.4	162.4
Net property, plant and equipment	32.5	51.9
Land, land improvements and logging roads, net of road amortization [Member]
Property, Plant and Equipment [Line Items]
Assets Held-for-sale, Property, Plant and Equipment	10.0	13.1
Building [Member]
Property, Plant and Equipment [Line Items]
Assets Held-for-sale, Property, Plant and Equipment	17.1	22.9
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Assets Held-for-sale, Property, Plant and Equipment	$ 140.8	$ 178.3