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Transactions With Related Parties (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 3.9		$ 3.9		$ 4.5
Carrying amount of LTP's liabilities	3.9		$ 3.9		$ 4.5
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	17.1	$ 23.2	$ 39.3	$ 45.1
Fiber costs from related parties	$ 4.5	$ 5.0	$ 9.2	$ 11.3
PCA
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage			50.00%