Amount included in cost of sales related to transactions with related parties incurred and recorded in the statement of operations for the period.

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Transactions With Related Parties - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 4.1		$ 4.1		$ 3.0
Carrying amount of LTP's liabilities	4.1		$ 4.1		$ 3.0
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	22.6	$ 21.7	$ 43.0	$ 45.2
Fiber costs from related parties	22.6	21.7	43.0	45.2
Boise Cascade Co-Owner of LTP \| Wood Products, Including Chips and Logs
Related Party Transaction [Line Items]
Fiber costs from related parties	$ 4.7	$ 4.6	$ 8.7	$ 9.6
Packaging Corporation of America
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage			50.00%