Investments in and Advances to Affiliates (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Related Party Transaction [Line Items]
Due from affiliates	$ 1.4	$ 0.5
Due to affiliates	6.7	2.3
Other-than-temporary impairment of investments	0	14.8	17.0
AbitibiBowater-LP [Member]
Related Party Transaction [Line Items]
Revenue from affiliates	8.7	6.0	5.6
AbitibiBowater-LP [Member] \| I Joist [Member]
Related Party Transaction [Line Items]
Expenses from affiliates	37.9	33.6	39.6
Canfor-LP [Member] \| OSB [Member]
Related Party Transaction [Line Items]
Expenses from affiliates	$ 148.0	$ 92.9	$ 109.5

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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