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Transactions With Related Parties (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 7.6		$ 7.6		$ 5.2
Carrying amount of LTP's liabilities	7.6		$ 7.6		$ 5.2
Boise Cascade Co-Owner of LTP
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage			50.00%
Boise Cascade Co-Owner of LTP \| Fiber
Related Party Transaction [Line Items]
Revenue from related parties	25.2	$ 21.9	$ 70.3	$ 56.9
Fiber costs from related parties	$ 5.0	$ 7.0	$ 16.3	$ 21.3
Packaging Corporation of America [Member]
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage			50.00%