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Transactions With Related Parties - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 8,344.4		$ 8,344.4		$ 7,836.8
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	23.1	$ 22.3	$ 67.4	$ 63.3
Boise Cascade Co-Owner of LTP \| Wood Products, Including Chips and Logs
Related Party Transaction [Line Items]
Fiber costs from related parties	3.4	$ 3.6	$ 10.7	$ 10.3
Packaging Corporation of America
Related Party Transaction [Line Items]
Variable interest entity, ownership percentage			50.00%
Variable Interest Entity
Related Party Transaction [Line Items]
Carrying amount of LTP's assets	$ 4.1		$ 4.1		$ 3.5