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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section 50
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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
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 2.9		$ 3.0
Carrying amount of LTP's liabilities	$ 2.9		$ 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	$ 20.5	$ 23.5
Fiber costs from related parties	20.5	23.5
Boise Cascade Co-Owner of LTP \| Wood Products, Including Chips and Logs
Related Party Transaction [Line Items]
Fiber costs from related parties	$ 4.0	$ 5.0
Packaging Corporation of America
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage	50.00%