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Transactions With Related Parties (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	6.2		$ 5.2
Carrying amount of LTP's liabilities	6.2		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	21.9	16.1
Fiber costs from related parties	6.3	$ 7.2
Packaging Corporation of America [Member]
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage	50.00%